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launch jvm gateway
:param conf: spark configuration passed to spark-submit
:param popen_kwargs: Dictionary of kwargs to pass to Popen when spawning
the py4j JVM. This is a developer feature intended for use in
customizing how pyspark interacts with the py4j JVM (e.g., capturing
stdout/stderr).
:return: | def launch_gateway(conf=None, popen_kwargs=None):
"""
launch jvm gateway
:param conf: spark configuration passed to spark-submit
:param popen_kwargs: Dictionary of kwargs to pass to Popen when spawning
the py4j JVM. This is a developer feature intended for use in
customizing how pyspark interacts with the py4j JVM (e.g., capturing
stdout/stderr).
:return:
"""
if "PYSPARK_GATEWAY_PORT" in os.environ:
gateway_port = int(os.environ["PYSPARK_GATEWAY_PORT"])
gateway_secret = os.environ["PYSPARK_GATEWAY_SECRET"]
# Process already exists
proc = None
else:
SPARK_HOME = _find_spark_home()
# Launch the Py4j gateway using Spark's run command so that we pick up the
# proper classpath and settings from spark-env.sh
on_windows = platform.system() == "Windows"
script = "./bin/spark-submit.cmd" if on_windows else "./bin/spark-submit"
command = [os.path.join(SPARK_HOME, script)]
if conf:
for k, v in conf.getAll():
command += ['--conf', '%s=%s' % (k, v)]
submit_args = os.environ.get("PYSPARK_SUBMIT_ARGS", "pyspark-shell")
if os.environ.get("SPARK_TESTING"):
submit_args = ' '.join([
"--conf spark.ui.enabled=false",
submit_args
])
command = command + shlex.split(submit_args)
# Create a temporary directory where the gateway server should write the connection
# information.
conn_info_dir = tempfile.mkdtemp()
try:
fd, conn_info_file = tempfile.mkstemp(dir=conn_info_dir)
os.close(fd)
os.unlink(conn_info_file)
env = dict(os.environ)
env["_PYSPARK_DRIVER_CONN_INFO_PATH"] = conn_info_file
# Launch the Java gateway.
popen_kwargs = {} if popen_kwargs is None else popen_kwargs
# We open a pipe to stdin so that the Java gateway can die when the pipe is broken
popen_kwargs['stdin'] = PIPE
# We always set the necessary environment variables.
popen_kwargs['env'] = env
if not on_windows:
# Don't send ctrl-c / SIGINT to the Java gateway:
def preexec_func():
signal.signal(signal.SIGINT, signal.SIG_IGN)
popen_kwargs['preexec_fn'] = preexec_func
proc = Popen(command, **popen_kwargs)
else:
# preexec_fn not supported on Windows
proc = Popen(command, **popen_kwargs)
# Wait for the file to appear, or for the process to exit, whichever happens first.
while not proc.poll() and not os.path.isfile(conn_info_file):
time.sleep(0.1)
if not os.path.isfile(conn_info_file):
raise Exception("Java gateway process exited before sending its port number")
with open(conn_info_file, "rb") as info:
gateway_port = read_int(info)
gateway_secret = UTF8Deserializer().loads(info)
finally:
shutil.rmtree(conn_info_dir)
# In Windows, ensure the Java child processes do not linger after Python has exited.
# In UNIX-based systems, the child process can kill itself on broken pipe (i.e. when
# the parent process' stdin sends an EOF). In Windows, however, this is not possible
# because java.lang.Process reads directly from the parent process' stdin, contending
# with any opportunity to read an EOF from the parent. Note that this is only best
# effort and will not take effect if the python process is violently terminated.
if on_windows:
# In Windows, the child process here is "spark-submit.cmd", not the JVM itself
# (because the UNIX "exec" command is not available). This means we cannot simply
# call proc.kill(), which kills only the "spark-submit.cmd" process but not the
# JVMs. Instead, we use "taskkill" with the tree-kill option "/t" to terminate all
# child processes in the tree (http://technet.microsoft.com/en-us/library/bb491009.aspx)
def killChild():
Popen(["cmd", "/c", "taskkill", "/f", "/t", "/pid", str(proc.pid)])
atexit.register(killChild)
# Connect to the gateway
gateway = JavaGateway(
gateway_parameters=GatewayParameters(port=gateway_port, auth_token=gateway_secret,
auto_convert=True))
# Store a reference to the Popen object for use by the caller (e.g., in reading stdout/stderr)
gateway.proc = proc
# Import the classes used by PySpark
java_import(gateway.jvm, "org.apache.spark.SparkConf")
java_import(gateway.jvm, "org.apache.spark.api.java.*")
java_import(gateway.jvm, "org.apache.spark.api.python.*")
java_import(gateway.jvm, "org.apache.spark.ml.python.*")
java_import(gateway.jvm, "org.apache.spark.mllib.api.python.*")
# TODO(davies): move into sql
java_import(gateway.jvm, "org.apache.spark.sql.*")
java_import(gateway.jvm, "org.apache.spark.sql.api.python.*")
java_import(gateway.jvm, "org.apache.spark.sql.hive.*")
java_import(gateway.jvm, "scala.Tuple2")
return gateway |
Performs the authentication protocol defined by the SocketAuthHelper class on the given
file-like object 'conn'. | def _do_server_auth(conn, auth_secret):
"""
Performs the authentication protocol defined by the SocketAuthHelper class on the given
file-like object 'conn'.
"""
write_with_length(auth_secret.encode("utf-8"), conn)
conn.flush()
reply = UTF8Deserializer().loads(conn)
if reply != "ok":
conn.close()
raise Exception("Unexpected reply from iterator server.") |
Connect to local host, authenticate with it, and return a (sockfile,sock) for that connection.
Handles IPV4 & IPV6, does some error handling.
:param port
:param auth_secret
:return: a tuple with (sockfile, sock) | def local_connect_and_auth(port, auth_secret):
"""
Connect to local host, authenticate with it, and return a (sockfile,sock) for that connection.
Handles IPV4 & IPV6, does some error handling.
:param port
:param auth_secret
:return: a tuple with (sockfile, sock)
"""
sock = None
errors = []
# Support for both IPv4 and IPv6.
# On most of IPv6-ready systems, IPv6 will take precedence.
for res in socket.getaddrinfo("127.0.0.1", port, socket.AF_UNSPEC, socket.SOCK_STREAM):
af, socktype, proto, _, sa = res
try:
sock = socket.socket(af, socktype, proto)
sock.settimeout(15)
sock.connect(sa)
sockfile = sock.makefile("rwb", 65536)
_do_server_auth(sockfile, auth_secret)
return (sockfile, sock)
except socket.error as e:
emsg = _exception_message(e)
errors.append("tried to connect to %s, but an error occured: %s" % (sa, emsg))
sock.close()
sock = None
raise Exception("could not open socket: %s" % errors) |
Start callback server if not already started. The callback server is needed if the Java
driver process needs to callback into the Python driver process to execute Python code. | def ensure_callback_server_started(gw):
"""
Start callback server if not already started. The callback server is needed if the Java
driver process needs to callback into the Python driver process to execute Python code.
"""
# getattr will fallback to JVM, so we cannot test by hasattr()
if "_callback_server" not in gw.__dict__ or gw._callback_server is None:
gw.callback_server_parameters.eager_load = True
gw.callback_server_parameters.daemonize = True
gw.callback_server_parameters.daemonize_connections = True
gw.callback_server_parameters.port = 0
gw.start_callback_server(gw.callback_server_parameters)
cbport = gw._callback_server.server_socket.getsockname()[1]
gw._callback_server.port = cbport
# gateway with real port
gw._python_proxy_port = gw._callback_server.port
# get the GatewayServer object in JVM by ID
jgws = JavaObject("GATEWAY_SERVER", gw._gateway_client)
# update the port of CallbackClient with real port
jgws.resetCallbackClient(jgws.getCallbackClient().getAddress(), gw._python_proxy_port) |
Find the SPARK_HOME. | def _find_spark_home():
"""Find the SPARK_HOME."""
# If the environment has SPARK_HOME set trust it.
if "SPARK_HOME" in os.environ:
return os.environ["SPARK_HOME"]
def is_spark_home(path):
"""Takes a path and returns true if the provided path could be a reasonable SPARK_HOME"""
return (os.path.isfile(os.path.join(path, "bin/spark-submit")) and
(os.path.isdir(os.path.join(path, "jars")) or
os.path.isdir(os.path.join(path, "assembly"))))
paths = ["../", os.path.dirname(os.path.realpath(__file__))]
# Add the path of the PySpark module if it exists
if sys.version < "3":
import imp
try:
module_home = imp.find_module("pyspark")[1]
paths.append(module_home)
# If we are installed in edit mode also look two dirs up
paths.append(os.path.join(module_home, "../../"))
except ImportError:
# Not pip installed no worries
pass
else:
from importlib.util import find_spec
try:
module_home = os.path.dirname(find_spec("pyspark").origin)
paths.append(module_home)
# If we are installed in edit mode also look two dirs up
paths.append(os.path.join(module_home, "../../"))
except ImportError:
# Not pip installed no worries
pass
# Normalize the paths
paths = [os.path.abspath(p) for p in paths]
try:
return next(path for path in paths if is_spark_home(path))
except StopIteration:
print("Could not find valid SPARK_HOME while searching {0}".format(paths), file=sys.stderr)
sys.exit(-1) |
Calculates URL contributions to the rank of other URLs. | def computeContribs(urls, rank):
"""Calculates URL contributions to the rank of other URLs."""
num_urls = len(urls)
for url in urls:
yield (url, rank / num_urls) |
Gets summary (e.g. cluster assignments, cluster sizes) of the model trained on the
training set. An exception is thrown if no summary exists. | def summary(self):
"""
Gets summary (e.g. cluster assignments, cluster sizes) of the model trained on the
training set. An exception is thrown if no summary exists.
"""
if self.hasSummary:
return GaussianMixtureSummary(super(GaussianMixtureModel, self).summary)
else:
raise RuntimeError("No training summary available for this %s" %
self.__class__.__name__) |
Gets summary (e.g. cluster assignments, cluster sizes) of the model trained on the
training set. An exception is thrown if no summary exists. | def summary(self):
"""
Gets summary (e.g. cluster assignments, cluster sizes) of the model trained on the
training set. An exception is thrown if no summary exists.
"""
if self.hasSummary:
return KMeansSummary(super(KMeansModel, self).summary)
else:
raise RuntimeError("No training summary available for this %s" %
self.__class__.__name__) |
Gets summary (e.g. cluster assignments, cluster sizes) of the model trained on the
training set. An exception is thrown if no summary exists. | def summary(self):
"""
Gets summary (e.g. cluster assignments, cluster sizes) of the model trained on the
training set. An exception is thrown if no summary exists.
"""
if self.hasSummary:
return BisectingKMeansSummary(super(BisectingKMeansModel, self).summary)
else:
raise RuntimeError("No training summary available for this %s" %
self.__class__.__name__) |
Returns the image schema.
:return: a :class:`StructType` with a single column of images
named "image" (nullable) and having the same type returned by :meth:`columnSchema`.
.. versionadded:: 2.3.0 | def imageSchema(self):
"""
Returns the image schema.
:return: a :class:`StructType` with a single column of images
named "image" (nullable) and having the same type returned by :meth:`columnSchema`.
.. versionadded:: 2.3.0
"""
if self._imageSchema is None:
ctx = SparkContext._active_spark_context
jschema = ctx._jvm.org.apache.spark.ml.image.ImageSchema.imageSchema()
self._imageSchema = _parse_datatype_json_string(jschema.json())
return self._imageSchema |
Returns the OpenCV type mapping supported.
:return: a dictionary containing the OpenCV type mapping supported.
.. versionadded:: 2.3.0 | def ocvTypes(self):
"""
Returns the OpenCV type mapping supported.
:return: a dictionary containing the OpenCV type mapping supported.
.. versionadded:: 2.3.0
"""
if self._ocvTypes is None:
ctx = SparkContext._active_spark_context
self._ocvTypes = dict(ctx._jvm.org.apache.spark.ml.image.ImageSchema.javaOcvTypes())
return self._ocvTypes |
Returns the schema for the image column.
:return: a :class:`StructType` for image column,
``struct<origin:string, height:int, width:int, nChannels:int, mode:int, data:binary>``.
.. versionadded:: 2.4.0 | def columnSchema(self):
"""
Returns the schema for the image column.
:return: a :class:`StructType` for image column,
``struct<origin:string, height:int, width:int, nChannels:int, mode:int, data:binary>``.
.. versionadded:: 2.4.0
"""
if self._columnSchema is None:
ctx = SparkContext._active_spark_context
jschema = ctx._jvm.org.apache.spark.ml.image.ImageSchema.columnSchema()
self._columnSchema = _parse_datatype_json_string(jschema.json())
return self._columnSchema |
Returns field names of image columns.
:return: a list of field names.
.. versionadded:: 2.3.0 | def imageFields(self):
"""
Returns field names of image columns.
:return: a list of field names.
.. versionadded:: 2.3.0
"""
if self._imageFields is None:
ctx = SparkContext._active_spark_context
self._imageFields = list(ctx._jvm.org.apache.spark.ml.image.ImageSchema.imageFields())
return self._imageFields |
Returns the name of undefined image type for the invalid image.
.. versionadded:: 2.3.0 | def undefinedImageType(self):
"""
Returns the name of undefined image type for the invalid image.
.. versionadded:: 2.3.0
"""
if self._undefinedImageType is None:
ctx = SparkContext._active_spark_context
self._undefinedImageType = \
ctx._jvm.org.apache.spark.ml.image.ImageSchema.undefinedImageType()
return self._undefinedImageType |
Converts an image to an array with metadata.
:param `Row` image: A row that contains the image to be converted. It should
have the attributes specified in `ImageSchema.imageSchema`.
:return: a `numpy.ndarray` that is an image.
.. versionadded:: 2.3.0 | def toNDArray(self, image):
"""
Converts an image to an array with metadata.
:param `Row` image: A row that contains the image to be converted. It should
have the attributes specified in `ImageSchema.imageSchema`.
:return: a `numpy.ndarray` that is an image.
.. versionadded:: 2.3.0
"""
if not isinstance(image, Row):
raise TypeError(
"image argument should be pyspark.sql.types.Row; however, "
"it got [%s]." % type(image))
if any(not hasattr(image, f) for f in self.imageFields):
raise ValueError(
"image argument should have attributes specified in "
"ImageSchema.imageSchema [%s]." % ", ".join(self.imageFields))
height = image.height
width = image.width
nChannels = image.nChannels
return np.ndarray(
shape=(height, width, nChannels),
dtype=np.uint8,
buffer=image.data,
strides=(width * nChannels, nChannels, 1)) |
Converts an array with metadata to a two-dimensional image.
:param `numpy.ndarray` array: The array to convert to image.
:param str origin: Path to the image, optional.
:return: a :class:`Row` that is a two dimensional image.
.. versionadded:: 2.3.0 | def toImage(self, array, origin=""):
"""
Converts an array with metadata to a two-dimensional image.
:param `numpy.ndarray` array: The array to convert to image.
:param str origin: Path to the image, optional.
:return: a :class:`Row` that is a two dimensional image.
.. versionadded:: 2.3.0
"""
if not isinstance(array, np.ndarray):
raise TypeError(
"array argument should be numpy.ndarray; however, it got [%s]." % type(array))
if array.ndim != 3:
raise ValueError("Invalid array shape")
height, width, nChannels = array.shape
ocvTypes = ImageSchema.ocvTypes
if nChannels == 1:
mode = ocvTypes["CV_8UC1"]
elif nChannels == 3:
mode = ocvTypes["CV_8UC3"]
elif nChannels == 4:
mode = ocvTypes["CV_8UC4"]
else:
raise ValueError("Invalid number of channels")
# Running `bytearray(numpy.array([1]))` fails in specific Python versions
# with a specific Numpy version, for example in Python 3.6.0 and NumPy 1.13.3.
# Here, it avoids it by converting it to bytes.
if LooseVersion(np.__version__) >= LooseVersion('1.9'):
data = bytearray(array.astype(dtype=np.uint8).ravel().tobytes())
else:
# Numpy prior to 1.9 don't have `tobytes` method.
data = bytearray(array.astype(dtype=np.uint8).ravel())
# Creating new Row with _create_row(), because Row(name = value, ... )
# orders fields by name, which conflicts with expected schema order
# when the new DataFrame is created by UDF
return _create_row(self.imageFields,
[origin, height, width, nChannels, mode, data]) |
Reads the directory of images from the local or remote source.
.. note:: If multiple jobs are run in parallel with different sampleRatio or recursive flag,
there may be a race condition where one job overwrites the hadoop configs of another.
.. note:: If sample ratio is less than 1, sampling uses a PathFilter that is efficient but
potentially non-deterministic.
.. note:: Deprecated in 2.4.0. Use `spark.read.format("image").load(path)` instead and
this `readImages` will be removed in 3.0.0.
:param str path: Path to the image directory.
:param bool recursive: Recursive search flag.
:param int numPartitions: Number of DataFrame partitions.
:param bool dropImageFailures: Drop the files that are not valid images.
:param float sampleRatio: Fraction of the images loaded.
:param int seed: Random number seed.
:return: a :class:`DataFrame` with a single column of "images",
see ImageSchema for details.
>>> df = ImageSchema.readImages('data/mllib/images/origin/kittens', recursive=True)
>>> df.count()
5
.. versionadded:: 2.3.0 | def readImages(self, path, recursive=False, numPartitions=-1,
dropImageFailures=False, sampleRatio=1.0, seed=0):
"""
Reads the directory of images from the local or remote source.
.. note:: If multiple jobs are run in parallel with different sampleRatio or recursive flag,
there may be a race condition where one job overwrites the hadoop configs of another.
.. note:: If sample ratio is less than 1, sampling uses a PathFilter that is efficient but
potentially non-deterministic.
.. note:: Deprecated in 2.4.0. Use `spark.read.format("image").load(path)` instead and
this `readImages` will be removed in 3.0.0.
:param str path: Path to the image directory.
:param bool recursive: Recursive search flag.
:param int numPartitions: Number of DataFrame partitions.
:param bool dropImageFailures: Drop the files that are not valid images.
:param float sampleRatio: Fraction of the images loaded.
:param int seed: Random number seed.
:return: a :class:`DataFrame` with a single column of "images",
see ImageSchema for details.
>>> df = ImageSchema.readImages('data/mllib/images/origin/kittens', recursive=True)
>>> df.count()
5
.. versionadded:: 2.3.0
"""
warnings.warn("`ImageSchema.readImage` is deprecated. " +
"Use `spark.read.format(\"image\").load(path)` instead.", DeprecationWarning)
spark = SparkSession.builder.getOrCreate()
image_schema = spark._jvm.org.apache.spark.ml.image.ImageSchema
jsession = spark._jsparkSession
jresult = image_schema.readImages(path, jsession, recursive, numPartitions,
dropImageFailures, float(sampleRatio), seed)
return DataFrame(jresult, spark._wrapped) |
Construct this object from given Java classname and arguments | def _create_from_java_class(cls, java_class, *args):
"""
Construct this object from given Java classname and arguments
"""
java_obj = JavaWrapper._new_java_obj(java_class, *args)
return cls(java_obj) |
Create a Java array of given java_class type. Useful for
calling a method with a Scala Array from Python with Py4J.
If the param pylist is a 2D array, then a 2D java array will be returned.
The returned 2D java array is a square, non-jagged 2D array that is big
enough for all elements. The empty slots in the inner Java arrays will
be filled with null to make the non-jagged 2D array.
:param pylist:
Python list to convert to a Java Array.
:param java_class:
Java class to specify the type of Array. Should be in the
form of sc._gateway.jvm.* (sc is a valid Spark Context).
:return:
Java Array of converted pylist.
Example primitive Java classes:
- basestring -> sc._gateway.jvm.java.lang.String
- int -> sc._gateway.jvm.java.lang.Integer
- float -> sc._gateway.jvm.java.lang.Double
- bool -> sc._gateway.jvm.java.lang.Boolean | def _new_java_array(pylist, java_class):
"""
Create a Java array of given java_class type. Useful for
calling a method with a Scala Array from Python with Py4J.
If the param pylist is a 2D array, then a 2D java array will be returned.
The returned 2D java array is a square, non-jagged 2D array that is big
enough for all elements. The empty slots in the inner Java arrays will
be filled with null to make the non-jagged 2D array.
:param pylist:
Python list to convert to a Java Array.
:param java_class:
Java class to specify the type of Array. Should be in the
form of sc._gateway.jvm.* (sc is a valid Spark Context).
:return:
Java Array of converted pylist.
Example primitive Java classes:
- basestring -> sc._gateway.jvm.java.lang.String
- int -> sc._gateway.jvm.java.lang.Integer
- float -> sc._gateway.jvm.java.lang.Double
- bool -> sc._gateway.jvm.java.lang.Boolean
"""
sc = SparkContext._active_spark_context
java_array = None
if len(pylist) > 0 and isinstance(pylist[0], list):
# If pylist is a 2D array, then a 2D java array will be created.
# The 2D array is a square, non-jagged 2D array that is big enough for all elements.
inner_array_length = 0
for i in xrange(len(pylist)):
inner_array_length = max(inner_array_length, len(pylist[i]))
java_array = sc._gateway.new_array(java_class, len(pylist), inner_array_length)
for i in xrange(len(pylist)):
for j in xrange(len(pylist[i])):
java_array[i][j] = pylist[i][j]
else:
java_array = sc._gateway.new_array(java_class, len(pylist))
for i in xrange(len(pylist)):
java_array[i] = pylist[i]
return java_array |
>>> _convert_epytext("L{A}")
:class:`A` | def _convert_epytext(line):
"""
>>> _convert_epytext("L{A}")
:class:`A`
"""
line = line.replace('@', ':')
for p, sub in RULES:
line = re.sub(p, sub, line)
return line |
Return string prefix-time(.suffix)
>>> rddToFileName("spark", None, 12345678910)
'spark-12345678910'
>>> rddToFileName("spark", "tmp", 12345678910)
'spark-12345678910.tmp' | def rddToFileName(prefix, suffix, timestamp):
"""
Return string prefix-time(.suffix)
>>> rddToFileName("spark", None, 12345678910)
'spark-12345678910'
>>> rddToFileName("spark", "tmp", 12345678910)
'spark-12345678910.tmp'
"""
if isinstance(timestamp, datetime):
seconds = time.mktime(timestamp.timetuple())
timestamp = int(seconds * 1000) + timestamp.microsecond // 1000
if suffix is None:
return prefix + "-" + str(timestamp)
else:
return prefix + "-" + str(timestamp) + "." + suffix |
Add a profiler for RDD `id` | def add_profiler(self, id, profiler):
""" Add a profiler for RDD `id` """
if not self.profilers:
if self.profile_dump_path:
atexit.register(self.dump_profiles, self.profile_dump_path)
else:
atexit.register(self.show_profiles)
self.profilers.append([id, profiler, False]) |
Dump the profile stats into directory `path` | def dump_profiles(self, path):
""" Dump the profile stats into directory `path` """
for id, profiler, _ in self.profilers:
profiler.dump(id, path)
self.profilers = [] |
Print the profile stats to stdout | def show_profiles(self):
""" Print the profile stats to stdout """
for i, (id, profiler, showed) in enumerate(self.profilers):
if not showed and profiler:
profiler.show(id)
# mark it as showed
self.profilers[i][2] = True |
Print the profile stats to stdout, id is the RDD id | def show(self, id):
""" Print the profile stats to stdout, id is the RDD id """
stats = self.stats()
if stats:
print("=" * 60)
print("Profile of RDD<id=%d>" % id)
print("=" * 60)
stats.sort_stats("time", "cumulative").print_stats() |
Dump the profile into path, id is the RDD id | def dump(self, id, path):
""" Dump the profile into path, id is the RDD id """
if not os.path.exists(path):
os.makedirs(path)
stats = self.stats()
if stats:
p = os.path.join(path, "rdd_%d.pstats" % id)
stats.dump_stats(p) |
Runs and profiles the method to_profile passed in. A profile object is returned. | def profile(self, func):
""" Runs and profiles the method to_profile passed in. A profile object is returned. """
pr = cProfile.Profile()
pr.runcall(func)
st = pstats.Stats(pr)
st.stream = None # make it picklable
st.strip_dirs()
# Adds a new profile to the existing accumulated value
self._accumulator.add(st) |
Get the existing SQLContext or create a new one with given SparkContext.
:param sc: SparkContext | def getOrCreate(cls, sc):
"""
Get the existing SQLContext or create a new one with given SparkContext.
:param sc: SparkContext
"""
if cls._instantiatedContext is None:
jsqlContext = sc._jvm.SQLContext.getOrCreate(sc._jsc.sc())
sparkSession = SparkSession(sc, jsqlContext.sparkSession())
cls(sc, sparkSession, jsqlContext)
return cls._instantiatedContext |
Sets the given Spark SQL configuration property. | def setConf(self, key, value):
"""Sets the given Spark SQL configuration property.
"""
self.sparkSession.conf.set(key, value) |
Returns the value of Spark SQL configuration property for the given key.
If the key is not set and defaultValue is set, return
defaultValue. If the key is not set and defaultValue is not set, return
the system default value.
>>> sqlContext.getConf("spark.sql.shuffle.partitions")
u'200'
>>> sqlContext.getConf("spark.sql.shuffle.partitions", u"10")
u'10'
>>> sqlContext.setConf("spark.sql.shuffle.partitions", u"50")
>>> sqlContext.getConf("spark.sql.shuffle.partitions", u"10")
u'50' | def getConf(self, key, defaultValue=_NoValue):
"""Returns the value of Spark SQL configuration property for the given key.
If the key is not set and defaultValue is set, return
defaultValue. If the key is not set and defaultValue is not set, return
the system default value.
>>> sqlContext.getConf("spark.sql.shuffle.partitions")
u'200'
>>> sqlContext.getConf("spark.sql.shuffle.partitions", u"10")
u'10'
>>> sqlContext.setConf("spark.sql.shuffle.partitions", u"50")
>>> sqlContext.getConf("spark.sql.shuffle.partitions", u"10")
u'50'
"""
return self.sparkSession.conf.get(key, defaultValue) |
Create a :class:`DataFrame` with single :class:`pyspark.sql.types.LongType` column named
``id``, containing elements in a range from ``start`` to ``end`` (exclusive) with
step value ``step``.
:param start: the start value
:param end: the end value (exclusive)
:param step: the incremental step (default: 1)
:param numPartitions: the number of partitions of the DataFrame
:return: :class:`DataFrame`
>>> sqlContext.range(1, 7, 2).collect()
[Row(id=1), Row(id=3), Row(id=5)]
If only one argument is specified, it will be used as the end value.
>>> sqlContext.range(3).collect()
[Row(id=0), Row(id=1), Row(id=2)] | def range(self, start, end=None, step=1, numPartitions=None):
"""
Create a :class:`DataFrame` with single :class:`pyspark.sql.types.LongType` column named
``id``, containing elements in a range from ``start`` to ``end`` (exclusive) with
step value ``step``.
:param start: the start value
:param end: the end value (exclusive)
:param step: the incremental step (default: 1)
:param numPartitions: the number of partitions of the DataFrame
:return: :class:`DataFrame`
>>> sqlContext.range(1, 7, 2).collect()
[Row(id=1), Row(id=3), Row(id=5)]
If only one argument is specified, it will be used as the end value.
>>> sqlContext.range(3).collect()
[Row(id=0), Row(id=1), Row(id=2)]
"""
return self.sparkSession.range(start, end, step, numPartitions) |
An alias for :func:`spark.udf.register`.
See :meth:`pyspark.sql.UDFRegistration.register`.
.. note:: Deprecated in 2.3.0. Use :func:`spark.udf.register` instead. | def registerFunction(self, name, f, returnType=None):
"""An alias for :func:`spark.udf.register`.
See :meth:`pyspark.sql.UDFRegistration.register`.
.. note:: Deprecated in 2.3.0. Use :func:`spark.udf.register` instead.
"""
warnings.warn(
"Deprecated in 2.3.0. Use spark.udf.register instead.",
DeprecationWarning)
return self.sparkSession.udf.register(name, f, returnType) |
An alias for :func:`spark.udf.registerJavaFunction`.
See :meth:`pyspark.sql.UDFRegistration.registerJavaFunction`.
.. note:: Deprecated in 2.3.0. Use :func:`spark.udf.registerJavaFunction` instead. | def registerJavaFunction(self, name, javaClassName, returnType=None):
"""An alias for :func:`spark.udf.registerJavaFunction`.
See :meth:`pyspark.sql.UDFRegistration.registerJavaFunction`.
.. note:: Deprecated in 2.3.0. Use :func:`spark.udf.registerJavaFunction` instead.
"""
warnings.warn(
"Deprecated in 2.3.0. Use spark.udf.registerJavaFunction instead.",
DeprecationWarning)
return self.sparkSession.udf.registerJavaFunction(name, javaClassName, returnType) |
Creates a :class:`DataFrame` from an :class:`RDD`, a list or a :class:`pandas.DataFrame`.
When ``schema`` is a list of column names, the type of each column
will be inferred from ``data``.
When ``schema`` is ``None``, it will try to infer the schema (column names and types)
from ``data``, which should be an RDD of :class:`Row`,
or :class:`namedtuple`, or :class:`dict`.
When ``schema`` is :class:`pyspark.sql.types.DataType` or a datatype string it must match
the real data, or an exception will be thrown at runtime. If the given schema is not
:class:`pyspark.sql.types.StructType`, it will be wrapped into a
:class:`pyspark.sql.types.StructType` as its only field, and the field name will be "value",
each record will also be wrapped into a tuple, which can be converted to row later.
If schema inference is needed, ``samplingRatio`` is used to determined the ratio of
rows used for schema inference. The first row will be used if ``samplingRatio`` is ``None``.
:param data: an RDD of any kind of SQL data representation(e.g. :class:`Row`,
:class:`tuple`, ``int``, ``boolean``, etc.), or :class:`list`, or
:class:`pandas.DataFrame`.
:param schema: a :class:`pyspark.sql.types.DataType` or a datatype string or a list of
column names, default is None. The data type string format equals to
:class:`pyspark.sql.types.DataType.simpleString`, except that top level struct type can
omit the ``struct<>`` and atomic types use ``typeName()`` as their format, e.g. use
``byte`` instead of ``tinyint`` for :class:`pyspark.sql.types.ByteType`.
We can also use ``int`` as a short name for :class:`pyspark.sql.types.IntegerType`.
:param samplingRatio: the sample ratio of rows used for inferring
:param verifySchema: verify data types of every row against schema.
:return: :class:`DataFrame`
.. versionchanged:: 2.0
The ``schema`` parameter can be a :class:`pyspark.sql.types.DataType` or a
datatype string after 2.0.
If it's not a :class:`pyspark.sql.types.StructType`, it will be wrapped into a
:class:`pyspark.sql.types.StructType` and each record will also be wrapped into a tuple.
.. versionchanged:: 2.1
Added verifySchema.
>>> l = [('Alice', 1)]
>>> sqlContext.createDataFrame(l).collect()
[Row(_1=u'Alice', _2=1)]
>>> sqlContext.createDataFrame(l, ['name', 'age']).collect()
[Row(name=u'Alice', age=1)]
>>> d = [{'name': 'Alice', 'age': 1}]
>>> sqlContext.createDataFrame(d).collect()
[Row(age=1, name=u'Alice')]
>>> rdd = sc.parallelize(l)
>>> sqlContext.createDataFrame(rdd).collect()
[Row(_1=u'Alice', _2=1)]
>>> df = sqlContext.createDataFrame(rdd, ['name', 'age'])
>>> df.collect()
[Row(name=u'Alice', age=1)]
>>> from pyspark.sql import Row
>>> Person = Row('name', 'age')
>>> person = rdd.map(lambda r: Person(*r))
>>> df2 = sqlContext.createDataFrame(person)
>>> df2.collect()
[Row(name=u'Alice', age=1)]
>>> from pyspark.sql.types import *
>>> schema = StructType([
... StructField("name", StringType(), True),
... StructField("age", IntegerType(), True)])
>>> df3 = sqlContext.createDataFrame(rdd, schema)
>>> df3.collect()
[Row(name=u'Alice', age=1)]
>>> sqlContext.createDataFrame(df.toPandas()).collect() # doctest: +SKIP
[Row(name=u'Alice', age=1)]
>>> sqlContext.createDataFrame(pandas.DataFrame([[1, 2]])).collect() # doctest: +SKIP
[Row(0=1, 1=2)]
>>> sqlContext.createDataFrame(rdd, "a: string, b: int").collect()
[Row(a=u'Alice', b=1)]
>>> rdd = rdd.map(lambda row: row[1])
>>> sqlContext.createDataFrame(rdd, "int").collect()
[Row(value=1)]
>>> sqlContext.createDataFrame(rdd, "boolean").collect() # doctest: +IGNORE_EXCEPTION_DETAIL
Traceback (most recent call last):
...
Py4JJavaError: ... | def createDataFrame(self, data, schema=None, samplingRatio=None, verifySchema=True):
"""
Creates a :class:`DataFrame` from an :class:`RDD`, a list or a :class:`pandas.DataFrame`.
When ``schema`` is a list of column names, the type of each column
will be inferred from ``data``.
When ``schema`` is ``None``, it will try to infer the schema (column names and types)
from ``data``, which should be an RDD of :class:`Row`,
or :class:`namedtuple`, or :class:`dict`.
When ``schema`` is :class:`pyspark.sql.types.DataType` or a datatype string it must match
the real data, or an exception will be thrown at runtime. If the given schema is not
:class:`pyspark.sql.types.StructType`, it will be wrapped into a
:class:`pyspark.sql.types.StructType` as its only field, and the field name will be "value",
each record will also be wrapped into a tuple, which can be converted to row later.
If schema inference is needed, ``samplingRatio`` is used to determined the ratio of
rows used for schema inference. The first row will be used if ``samplingRatio`` is ``None``.
:param data: an RDD of any kind of SQL data representation(e.g. :class:`Row`,
:class:`tuple`, ``int``, ``boolean``, etc.), or :class:`list`, or
:class:`pandas.DataFrame`.
:param schema: a :class:`pyspark.sql.types.DataType` or a datatype string or a list of
column names, default is None. The data type string format equals to
:class:`pyspark.sql.types.DataType.simpleString`, except that top level struct type can
omit the ``struct<>`` and atomic types use ``typeName()`` as their format, e.g. use
``byte`` instead of ``tinyint`` for :class:`pyspark.sql.types.ByteType`.
We can also use ``int`` as a short name for :class:`pyspark.sql.types.IntegerType`.
:param samplingRatio: the sample ratio of rows used for inferring
:param verifySchema: verify data types of every row against schema.
:return: :class:`DataFrame`
.. versionchanged:: 2.0
The ``schema`` parameter can be a :class:`pyspark.sql.types.DataType` or a
datatype string after 2.0.
If it's not a :class:`pyspark.sql.types.StructType`, it will be wrapped into a
:class:`pyspark.sql.types.StructType` and each record will also be wrapped into a tuple.
.. versionchanged:: 2.1
Added verifySchema.
>>> l = [('Alice', 1)]
>>> sqlContext.createDataFrame(l).collect()
[Row(_1=u'Alice', _2=1)]
>>> sqlContext.createDataFrame(l, ['name', 'age']).collect()
[Row(name=u'Alice', age=1)]
>>> d = [{'name': 'Alice', 'age': 1}]
>>> sqlContext.createDataFrame(d).collect()
[Row(age=1, name=u'Alice')]
>>> rdd = sc.parallelize(l)
>>> sqlContext.createDataFrame(rdd).collect()
[Row(_1=u'Alice', _2=1)]
>>> df = sqlContext.createDataFrame(rdd, ['name', 'age'])
>>> df.collect()
[Row(name=u'Alice', age=1)]
>>> from pyspark.sql import Row
>>> Person = Row('name', 'age')
>>> person = rdd.map(lambda r: Person(*r))
>>> df2 = sqlContext.createDataFrame(person)
>>> df2.collect()
[Row(name=u'Alice', age=1)]
>>> from pyspark.sql.types import *
>>> schema = StructType([
... StructField("name", StringType(), True),
... StructField("age", IntegerType(), True)])
>>> df3 = sqlContext.createDataFrame(rdd, schema)
>>> df3.collect()
[Row(name=u'Alice', age=1)]
>>> sqlContext.createDataFrame(df.toPandas()).collect() # doctest: +SKIP
[Row(name=u'Alice', age=1)]
>>> sqlContext.createDataFrame(pandas.DataFrame([[1, 2]])).collect() # doctest: +SKIP
[Row(0=1, 1=2)]
>>> sqlContext.createDataFrame(rdd, "a: string, b: int").collect()
[Row(a=u'Alice', b=1)]
>>> rdd = rdd.map(lambda row: row[1])
>>> sqlContext.createDataFrame(rdd, "int").collect()
[Row(value=1)]
>>> sqlContext.createDataFrame(rdd, "boolean").collect() # doctest: +IGNORE_EXCEPTION_DETAIL
Traceback (most recent call last):
...
Py4JJavaError: ...
"""
return self.sparkSession.createDataFrame(data, schema, samplingRatio, verifySchema) |
Creates an external table based on the dataset in a data source.
It returns the DataFrame associated with the external table.
The data source is specified by the ``source`` and a set of ``options``.
If ``source`` is not specified, the default data source configured by
``spark.sql.sources.default`` will be used.
Optionally, a schema can be provided as the schema of the returned :class:`DataFrame` and
created external table.
:return: :class:`DataFrame` | def createExternalTable(self, tableName, path=None, source=None, schema=None, **options):
"""Creates an external table based on the dataset in a data source.
It returns the DataFrame associated with the external table.
The data source is specified by the ``source`` and a set of ``options``.
If ``source`` is not specified, the default data source configured by
``spark.sql.sources.default`` will be used.
Optionally, a schema can be provided as the schema of the returned :class:`DataFrame` and
created external table.
:return: :class:`DataFrame`
"""
return self.sparkSession.catalog.createExternalTable(
tableName, path, source, schema, **options) |
Returns a :class:`DataFrame` containing names of tables in the given database.
If ``dbName`` is not specified, the current database will be used.
The returned DataFrame has two columns: ``tableName`` and ``isTemporary``
(a column with :class:`BooleanType` indicating if a table is a temporary one or not).
:param dbName: string, name of the database to use.
:return: :class:`DataFrame`
>>> sqlContext.registerDataFrameAsTable(df, "table1")
>>> df2 = sqlContext.tables()
>>> df2.filter("tableName = 'table1'").first()
Row(database=u'', tableName=u'table1', isTemporary=True) | def tables(self, dbName=None):
"""Returns a :class:`DataFrame` containing names of tables in the given database.
If ``dbName`` is not specified, the current database will be used.
The returned DataFrame has two columns: ``tableName`` and ``isTemporary``
(a column with :class:`BooleanType` indicating if a table is a temporary one or not).
:param dbName: string, name of the database to use.
:return: :class:`DataFrame`
>>> sqlContext.registerDataFrameAsTable(df, "table1")
>>> df2 = sqlContext.tables()
>>> df2.filter("tableName = 'table1'").first()
Row(database=u'', tableName=u'table1', isTemporary=True)
"""
if dbName is None:
return DataFrame(self._ssql_ctx.tables(), self)
else:
return DataFrame(self._ssql_ctx.tables(dbName), self) |
Returns a list of names of tables in the database ``dbName``.
:param dbName: string, name of the database to use. Default to the current database.
:return: list of table names, in string
>>> sqlContext.registerDataFrameAsTable(df, "table1")
>>> "table1" in sqlContext.tableNames()
True
>>> "table1" in sqlContext.tableNames("default")
True | def tableNames(self, dbName=None):
"""Returns a list of names of tables in the database ``dbName``.
:param dbName: string, name of the database to use. Default to the current database.
:return: list of table names, in string
>>> sqlContext.registerDataFrameAsTable(df, "table1")
>>> "table1" in sqlContext.tableNames()
True
>>> "table1" in sqlContext.tableNames("default")
True
"""
if dbName is None:
return [name for name in self._ssql_ctx.tableNames()]
else:
return [name for name in self._ssql_ctx.tableNames(dbName)] |
Returns a :class:`StreamingQueryManager` that allows managing all the
:class:`StreamingQuery` StreamingQueries active on `this` context.
.. note:: Evolving. | def streams(self):
"""Returns a :class:`StreamingQueryManager` that allows managing all the
:class:`StreamingQuery` StreamingQueries active on `this` context.
.. note:: Evolving.
"""
from pyspark.sql.streaming import StreamingQueryManager
return StreamingQueryManager(self._ssql_ctx.streams()) |
Converts a binary column of avro format into its corresponding catalyst value. The specified
schema must match the read data, otherwise the behavior is undefined: it may fail or return
arbitrary result.
Note: Avro is built-in but external data source module since Spark 2.4. Please deploy the
application as per the deployment section of "Apache Avro Data Source Guide".
:param data: the binary column.
:param jsonFormatSchema: the avro schema in JSON string format.
:param options: options to control how the Avro record is parsed.
>>> from pyspark.sql import Row
>>> from pyspark.sql.avro.functions import from_avro, to_avro
>>> data = [(1, Row(name='Alice', age=2))]
>>> df = spark.createDataFrame(data, ("key", "value"))
>>> avroDf = df.select(to_avro(df.value).alias("avro"))
>>> avroDf.collect()
[Row(avro=bytearray(b'\\x00\\x00\\x04\\x00\\nAlice'))]
>>> jsonFormatSchema = '''{"type":"record","name":"topLevelRecord","fields":
... [{"name":"avro","type":[{"type":"record","name":"value","namespace":"topLevelRecord",
... "fields":[{"name":"age","type":["long","null"]},
... {"name":"name","type":["string","null"]}]},"null"]}]}'''
>>> avroDf.select(from_avro(avroDf.avro, jsonFormatSchema).alias("value")).collect()
[Row(value=Row(avro=Row(age=2, name=u'Alice')))] | def from_avro(data, jsonFormatSchema, options={}):
"""
Converts a binary column of avro format into its corresponding catalyst value. The specified
schema must match the read data, otherwise the behavior is undefined: it may fail or return
arbitrary result.
Note: Avro is built-in but external data source module since Spark 2.4. Please deploy the
application as per the deployment section of "Apache Avro Data Source Guide".
:param data: the binary column.
:param jsonFormatSchema: the avro schema in JSON string format.
:param options: options to control how the Avro record is parsed.
>>> from pyspark.sql import Row
>>> from pyspark.sql.avro.functions import from_avro, to_avro
>>> data = [(1, Row(name='Alice', age=2))]
>>> df = spark.createDataFrame(data, ("key", "value"))
>>> avroDf = df.select(to_avro(df.value).alias("avro"))
>>> avroDf.collect()
[Row(avro=bytearray(b'\\x00\\x00\\x04\\x00\\nAlice'))]
>>> jsonFormatSchema = '''{"type":"record","name":"topLevelRecord","fields":
... [{"name":"avro","type":[{"type":"record","name":"value","namespace":"topLevelRecord",
... "fields":[{"name":"age","type":["long","null"]},
... {"name":"name","type":["string","null"]}]},"null"]}]}'''
>>> avroDf.select(from_avro(avroDf.avro, jsonFormatSchema).alias("value")).collect()
[Row(value=Row(avro=Row(age=2, name=u'Alice')))]
"""
sc = SparkContext._active_spark_context
try:
jc = sc._jvm.org.apache.spark.sql.avro.functions.from_avro(
_to_java_column(data), jsonFormatSchema, options)
except TypeError as e:
if str(e) == "'JavaPackage' object is not callable":
_print_missing_jar("Avro", "avro", "avro", sc.version)
raise
return Column(jc) |
Get the absolute path of a file added through C{SparkContext.addFile()}. | def get(cls, filename):
"""
Get the absolute path of a file added through C{SparkContext.addFile()}.
"""
path = os.path.join(SparkFiles.getRootDirectory(), filename)
return os.path.abspath(path) |
Get the root directory that contains files added through
C{SparkContext.addFile()}. | def getRootDirectory(cls):
"""
Get the root directory that contains files added through
C{SparkContext.addFile()}.
"""
if cls._is_running_on_worker:
return cls._root_directory
else:
# This will have to change if we support multiple SparkContexts:
return cls._sc._jvm.org.apache.spark.SparkFiles.getRootDirectory() |
Gets summary (e.g. accuracy/precision/recall, objective history, total iterations) of model
trained on the training set. An exception is thrown if `trainingSummary is None`. | def summary(self):
"""
Gets summary (e.g. accuracy/precision/recall, objective history, total iterations) of model
trained on the training set. An exception is thrown if `trainingSummary is None`.
"""
if self.hasSummary:
if self.numClasses <= 2:
return BinaryLogisticRegressionTrainingSummary(super(LogisticRegressionModel,
self).summary)
else:
return LogisticRegressionTrainingSummary(super(LogisticRegressionModel,
self).summary)
else:
raise RuntimeError("No training summary available for this %s" %
self.__class__.__name__) |
Evaluates the model on a test dataset.
:param dataset:
Test dataset to evaluate model on, where dataset is an
instance of :py:class:`pyspark.sql.DataFrame` | def evaluate(self, dataset):
"""
Evaluates the model on a test dataset.
:param dataset:
Test dataset to evaluate model on, where dataset is an
instance of :py:class:`pyspark.sql.DataFrame`
"""
if not isinstance(dataset, DataFrame):
raise ValueError("dataset must be a DataFrame but got %s." % type(dataset))
java_blr_summary = self._call_java("evaluate", dataset)
return BinaryLogisticRegressionSummary(java_blr_summary) |
Creates a copy of this instance with a randomly generated uid
and some extra params. This creates a deep copy of the embedded paramMap,
and copies the embedded and extra parameters over.
:param extra: Extra parameters to copy to the new instance
:return: Copy of this instance | def copy(self, extra=None):
"""
Creates a copy of this instance with a randomly generated uid
and some extra params. This creates a deep copy of the embedded paramMap,
and copies the embedded and extra parameters over.
:param extra: Extra parameters to copy to the new instance
:return: Copy of this instance
"""
if extra is None:
extra = dict()
newModel = Params.copy(self, extra)
newModel.models = [model.copy(extra) for model in self.models]
return newModel |
Given a Java OneVsRestModel, create and return a Python wrapper of it.
Used for ML persistence. | def _from_java(cls, java_stage):
"""
Given a Java OneVsRestModel, create and return a Python wrapper of it.
Used for ML persistence.
"""
featuresCol = java_stage.getFeaturesCol()
labelCol = java_stage.getLabelCol()
predictionCol = java_stage.getPredictionCol()
classifier = JavaParams._from_java(java_stage.getClassifier())
models = [JavaParams._from_java(model) for model in java_stage.models()]
py_stage = cls(models=models).setPredictionCol(predictionCol).setLabelCol(labelCol)\
.setFeaturesCol(featuresCol).setClassifier(classifier)
py_stage._resetUid(java_stage.uid())
return py_stage |
Transfer this instance to a Java OneVsRestModel. Used for ML persistence.
:return: Java object equivalent to this instance. | def _to_java(self):
"""
Transfer this instance to a Java OneVsRestModel. Used for ML persistence.
:return: Java object equivalent to this instance.
"""
sc = SparkContext._active_spark_context
java_models = [model._to_java() for model in self.models]
java_models_array = JavaWrapper._new_java_array(
java_models, sc._gateway.jvm.org.apache.spark.ml.classification.ClassificationModel)
metadata = JavaParams._new_java_obj("org.apache.spark.sql.types.Metadata")
_java_obj = JavaParams._new_java_obj("org.apache.spark.ml.classification.OneVsRestModel",
self.uid, metadata.empty(), java_models_array)
_java_obj.set("classifier", self.getClassifier()._to_java())
_java_obj.set("featuresCol", self.getFeaturesCol())
_java_obj.set("labelCol", self.getLabelCol())
_java_obj.set("predictionCol", self.getPredictionCol())
return _java_obj |
Return the message from an exception as either a str or unicode object. Supports both
Python 2 and Python 3.
>>> msg = "Exception message"
>>> excp = Exception(msg)
>>> msg == _exception_message(excp)
True
>>> msg = u"unicöde"
>>> excp = Exception(msg)
>>> msg == _exception_message(excp)
True | def _exception_message(excp):
"""Return the message from an exception as either a str or unicode object. Supports both
Python 2 and Python 3.
>>> msg = "Exception message"
>>> excp = Exception(msg)
>>> msg == _exception_message(excp)
True
>>> msg = u"unicöde"
>>> excp = Exception(msg)
>>> msg == _exception_message(excp)
True
"""
if isinstance(excp, Py4JJavaError):
# 'Py4JJavaError' doesn't contain the stack trace available on the Java side in 'message'
# attribute in Python 2. We should call 'str' function on this exception in general but
# 'Py4JJavaError' has an issue about addressing non-ascii strings. So, here we work
# around by the direct call, '__str__()'. Please see SPARK-23517.
return excp.__str__()
if hasattr(excp, "message"):
return excp.message
return str(excp) |
Get argspec of a function. Supports both Python 2 and Python 3. | def _get_argspec(f):
"""
Get argspec of a function. Supports both Python 2 and Python 3.
"""
if sys.version_info[0] < 3:
argspec = inspect.getargspec(f)
else:
# `getargspec` is deprecated since python3.0 (incompatible with function annotations).
# See SPARK-23569.
argspec = inspect.getfullargspec(f)
return argspec |
Wraps the input function to fail on 'StopIteration' by raising a 'RuntimeError'
prevents silent loss of data when 'f' is used in a for loop in Spark code | def fail_on_stopiteration(f):
"""
Wraps the input function to fail on 'StopIteration' by raising a 'RuntimeError'
prevents silent loss of data when 'f' is used in a for loop in Spark code
"""
def wrapper(*args, **kwargs):
try:
return f(*args, **kwargs)
except StopIteration as exc:
raise RuntimeError(
"Caught StopIteration thrown from user's code; failing the task",
exc
)
return wrapper |
Given a Spark version string, return the (major version number, minor version number).
E.g., for 2.0.1-SNAPSHOT, return (2, 0).
>>> sparkVersion = "2.4.0"
>>> VersionUtils.majorMinorVersion(sparkVersion)
(2, 4)
>>> sparkVersion = "2.3.0-SNAPSHOT"
>>> VersionUtils.majorMinorVersion(sparkVersion)
(2, 3) | def majorMinorVersion(sparkVersion):
"""
Given a Spark version string, return the (major version number, minor version number).
E.g., for 2.0.1-SNAPSHOT, return (2, 0).
>>> sparkVersion = "2.4.0"
>>> VersionUtils.majorMinorVersion(sparkVersion)
(2, 4)
>>> sparkVersion = "2.3.0-SNAPSHOT"
>>> VersionUtils.majorMinorVersion(sparkVersion)
(2, 3)
"""
m = re.search(r'^(\d+)\.(\d+)(\..*)?$', sparkVersion)
if m is not None:
return (int(m.group(1)), int(m.group(2)))
else:
raise ValueError("Spark tried to parse '%s' as a Spark" % sparkVersion +
" version string, but it could not find the major and minor" +
" version numbers.") |
Checks whether a SparkContext is initialized or not.
Throws error if a SparkContext is already running. | def _ensure_initialized(cls, instance=None, gateway=None, conf=None):
"""
Checks whether a SparkContext is initialized or not.
Throws error if a SparkContext is already running.
"""
with SparkContext._lock:
if not SparkContext._gateway:
SparkContext._gateway = gateway or launch_gateway(conf)
SparkContext._jvm = SparkContext._gateway.jvm
if instance:
if (SparkContext._active_spark_context and
SparkContext._active_spark_context != instance):
currentMaster = SparkContext._active_spark_context.master
currentAppName = SparkContext._active_spark_context.appName
callsite = SparkContext._active_spark_context._callsite
# Raise error if there is already a running Spark context
raise ValueError(
"Cannot run multiple SparkContexts at once; "
"existing SparkContext(app=%s, master=%s)"
" created by %s at %s:%s "
% (currentAppName, currentMaster,
callsite.function, callsite.file, callsite.linenum))
else:
SparkContext._active_spark_context = instance |
Get or instantiate a SparkContext and register it as a singleton object.
:param conf: SparkConf (optional) | def getOrCreate(cls, conf=None):
"""
Get or instantiate a SparkContext and register it as a singleton object.
:param conf: SparkConf (optional)
"""
with SparkContext._lock:
if SparkContext._active_spark_context is None:
SparkContext(conf=conf or SparkConf())
return SparkContext._active_spark_context |
Set a Java system property, such as spark.executor.memory. This must
must be invoked before instantiating SparkContext. | def setSystemProperty(cls, key, value):
"""
Set a Java system property, such as spark.executor.memory. This must
must be invoked before instantiating SparkContext.
"""
SparkContext._ensure_initialized()
SparkContext._jvm.java.lang.System.setProperty(key, value) |
Shut down the SparkContext. | def stop(self):
"""
Shut down the SparkContext.
"""
if getattr(self, "_jsc", None):
try:
self._jsc.stop()
except Py4JError:
# Case: SPARK-18523
warnings.warn(
'Unable to cleanly shutdown Spark JVM process.'
' It is possible that the process has crashed,'
' been killed or may also be in a zombie state.',
RuntimeWarning
)
finally:
self._jsc = None
if getattr(self, "_accumulatorServer", None):
self._accumulatorServer.shutdown()
self._accumulatorServer = None
with SparkContext._lock:
SparkContext._active_spark_context = None |
Create a new RDD of int containing elements from `start` to `end`
(exclusive), increased by `step` every element. Can be called the same
way as python's built-in range() function. If called with a single argument,
the argument is interpreted as `end`, and `start` is set to 0.
:param start: the start value
:param end: the end value (exclusive)
:param step: the incremental step (default: 1)
:param numSlices: the number of partitions of the new RDD
:return: An RDD of int
>>> sc.range(5).collect()
[0, 1, 2, 3, 4]
>>> sc.range(2, 4).collect()
[2, 3]
>>> sc.range(1, 7, 2).collect()
[1, 3, 5] | def range(self, start, end=None, step=1, numSlices=None):
"""
Create a new RDD of int containing elements from `start` to `end`
(exclusive), increased by `step` every element. Can be called the same
way as python's built-in range() function. If called with a single argument,
the argument is interpreted as `end`, and `start` is set to 0.
:param start: the start value
:param end: the end value (exclusive)
:param step: the incremental step (default: 1)
:param numSlices: the number of partitions of the new RDD
:return: An RDD of int
>>> sc.range(5).collect()
[0, 1, 2, 3, 4]
>>> sc.range(2, 4).collect()
[2, 3]
>>> sc.range(1, 7, 2).collect()
[1, 3, 5]
"""
if end is None:
end = start
start = 0
return self.parallelize(xrange(start, end, step), numSlices) |
Distribute a local Python collection to form an RDD. Using xrange
is recommended if the input represents a range for performance.
>>> sc.parallelize([0, 2, 3, 4, 6], 5).glom().collect()
[[0], [2], [3], [4], [6]]
>>> sc.parallelize(xrange(0, 6, 2), 5).glom().collect()
[[], [0], [], [2], [4]] | def parallelize(self, c, numSlices=None):
"""
Distribute a local Python collection to form an RDD. Using xrange
is recommended if the input represents a range for performance.
>>> sc.parallelize([0, 2, 3, 4, 6], 5).glom().collect()
[[0], [2], [3], [4], [6]]
>>> sc.parallelize(xrange(0, 6, 2), 5).glom().collect()
[[], [0], [], [2], [4]]
"""
numSlices = int(numSlices) if numSlices is not None else self.defaultParallelism
if isinstance(c, xrange):
size = len(c)
if size == 0:
return self.parallelize([], numSlices)
step = c[1] - c[0] if size > 1 else 1
start0 = c[0]
def getStart(split):
return start0 + int((split * size / numSlices)) * step
def f(split, iterator):
# it's an empty iterator here but we need this line for triggering the
# logic of signal handling in FramedSerializer.load_stream, for instance,
# SpecialLengths.END_OF_DATA_SECTION in _read_with_length. Since
# FramedSerializer.load_stream produces a generator, the control should
# at least be in that function once. Here we do it by explicitly converting
# the empty iterator to a list, thus make sure worker reuse takes effect.
# See more details in SPARK-26549.
assert len(list(iterator)) == 0
return xrange(getStart(split), getStart(split + 1), step)
return self.parallelize([], numSlices).mapPartitionsWithIndex(f)
# Make sure we distribute data evenly if it's smaller than self.batchSize
if "__len__" not in dir(c):
c = list(c) # Make it a list so we can compute its length
batchSize = max(1, min(len(c) // numSlices, self._batchSize or 1024))
serializer = BatchedSerializer(self._unbatched_serializer, batchSize)
def reader_func(temp_filename):
return self._jvm.PythonRDD.readRDDFromFile(self._jsc, temp_filename, numSlices)
def createRDDServer():
return self._jvm.PythonParallelizeServer(self._jsc.sc(), numSlices)
jrdd = self._serialize_to_jvm(c, serializer, reader_func, createRDDServer)
return RDD(jrdd, self, serializer) |
Using py4j to send a large dataset to the jvm is really slow, so we use either a file
or a socket if we have encryption enabled.
:param data:
:param serializer:
:param reader_func: A function which takes a filename and reads in the data in the jvm and
returns a JavaRDD. Only used when encryption is disabled.
:param createRDDServer: A function which creates a PythonRDDServer in the jvm to
accept the serialized data, for use when encryption is enabled.
:return: | def _serialize_to_jvm(self, data, serializer, reader_func, createRDDServer):
"""
Using py4j to send a large dataset to the jvm is really slow, so we use either a file
or a socket if we have encryption enabled.
:param data:
:param serializer:
:param reader_func: A function which takes a filename and reads in the data in the jvm and
returns a JavaRDD. Only used when encryption is disabled.
:param createRDDServer: A function which creates a PythonRDDServer in the jvm to
accept the serialized data, for use when encryption is enabled.
:return:
"""
if self._encryption_enabled:
# with encryption, we open a server in java and send the data directly
server = createRDDServer()
(sock_file, _) = local_connect_and_auth(server.port(), server.secret())
chunked_out = ChunkedStream(sock_file, 8192)
serializer.dump_stream(data, chunked_out)
chunked_out.close()
# this call will block until the server has read all the data and processed it (or
# throws an exception)
r = server.getResult()
return r
else:
# without encryption, we serialize to a file, and we read the file in java and
# parallelize from there.
tempFile = NamedTemporaryFile(delete=False, dir=self._temp_dir)
try:
try:
serializer.dump_stream(data, tempFile)
finally:
tempFile.close()
return reader_func(tempFile.name)
finally:
# we eagerily reads the file so we can delete right after.
os.unlink(tempFile.name) |
Load an RDD previously saved using L{RDD.saveAsPickleFile} method.
>>> tmpFile = NamedTemporaryFile(delete=True)
>>> tmpFile.close()
>>> sc.parallelize(range(10)).saveAsPickleFile(tmpFile.name, 5)
>>> sorted(sc.pickleFile(tmpFile.name, 3).collect())
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9] | def pickleFile(self, name, minPartitions=None):
"""
Load an RDD previously saved using L{RDD.saveAsPickleFile} method.
>>> tmpFile = NamedTemporaryFile(delete=True)
>>> tmpFile.close()
>>> sc.parallelize(range(10)).saveAsPickleFile(tmpFile.name, 5)
>>> sorted(sc.pickleFile(tmpFile.name, 3).collect())
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
"""
minPartitions = minPartitions or self.defaultMinPartitions
return RDD(self._jsc.objectFile(name, minPartitions), self) |
Read a text file from HDFS, a local file system (available on all
nodes), or any Hadoop-supported file system URI, and return it as an
RDD of Strings.
The text files must be encoded as UTF-8.
If use_unicode is False, the strings will be kept as `str` (encoding
as `utf-8`), which is faster and smaller than unicode. (Added in
Spark 1.2)
>>> path = os.path.join(tempdir, "sample-text.txt")
>>> with open(path, "w") as testFile:
... _ = testFile.write("Hello world!")
>>> textFile = sc.textFile(path)
>>> textFile.collect()
[u'Hello world!'] | def textFile(self, name, minPartitions=None, use_unicode=True):
"""
Read a text file from HDFS, a local file system (available on all
nodes), or any Hadoop-supported file system URI, and return it as an
RDD of Strings.
The text files must be encoded as UTF-8.
If use_unicode is False, the strings will be kept as `str` (encoding
as `utf-8`), which is faster and smaller than unicode. (Added in
Spark 1.2)
>>> path = os.path.join(tempdir, "sample-text.txt")
>>> with open(path, "w") as testFile:
... _ = testFile.write("Hello world!")
>>> textFile = sc.textFile(path)
>>> textFile.collect()
[u'Hello world!']
"""
minPartitions = minPartitions or min(self.defaultParallelism, 2)
return RDD(self._jsc.textFile(name, minPartitions), self,
UTF8Deserializer(use_unicode)) |
Read a directory of text files from HDFS, a local file system
(available on all nodes), or any Hadoop-supported file system
URI. Each file is read as a single record and returned in a
key-value pair, where the key is the path of each file, the
value is the content of each file.
The text files must be encoded as UTF-8.
If use_unicode is False, the strings will be kept as `str` (encoding
as `utf-8`), which is faster and smaller than unicode. (Added in
Spark 1.2)
For example, if you have the following files::
hdfs://a-hdfs-path/part-00000
hdfs://a-hdfs-path/part-00001
...
hdfs://a-hdfs-path/part-nnnnn
Do C{rdd = sparkContext.wholeTextFiles("hdfs://a-hdfs-path")},
then C{rdd} contains::
(a-hdfs-path/part-00000, its content)
(a-hdfs-path/part-00001, its content)
...
(a-hdfs-path/part-nnnnn, its content)
.. note:: Small files are preferred, as each file will be loaded
fully in memory.
>>> dirPath = os.path.join(tempdir, "files")
>>> os.mkdir(dirPath)
>>> with open(os.path.join(dirPath, "1.txt"), "w") as file1:
... _ = file1.write("1")
>>> with open(os.path.join(dirPath, "2.txt"), "w") as file2:
... _ = file2.write("2")
>>> textFiles = sc.wholeTextFiles(dirPath)
>>> sorted(textFiles.collect())
[(u'.../1.txt', u'1'), (u'.../2.txt', u'2')] | def wholeTextFiles(self, path, minPartitions=None, use_unicode=True):
"""
Read a directory of text files from HDFS, a local file system
(available on all nodes), or any Hadoop-supported file system
URI. Each file is read as a single record and returned in a
key-value pair, where the key is the path of each file, the
value is the content of each file.
The text files must be encoded as UTF-8.
If use_unicode is False, the strings will be kept as `str` (encoding
as `utf-8`), which is faster and smaller than unicode. (Added in
Spark 1.2)
For example, if you have the following files::
hdfs://a-hdfs-path/part-00000
hdfs://a-hdfs-path/part-00001
...
hdfs://a-hdfs-path/part-nnnnn
Do C{rdd = sparkContext.wholeTextFiles("hdfs://a-hdfs-path")},
then C{rdd} contains::
(a-hdfs-path/part-00000, its content)
(a-hdfs-path/part-00001, its content)
...
(a-hdfs-path/part-nnnnn, its content)
.. note:: Small files are preferred, as each file will be loaded
fully in memory.
>>> dirPath = os.path.join(tempdir, "files")
>>> os.mkdir(dirPath)
>>> with open(os.path.join(dirPath, "1.txt"), "w") as file1:
... _ = file1.write("1")
>>> with open(os.path.join(dirPath, "2.txt"), "w") as file2:
... _ = file2.write("2")
>>> textFiles = sc.wholeTextFiles(dirPath)
>>> sorted(textFiles.collect())
[(u'.../1.txt', u'1'), (u'.../2.txt', u'2')]
"""
minPartitions = minPartitions or self.defaultMinPartitions
return RDD(self._jsc.wholeTextFiles(path, minPartitions), self,
PairDeserializer(UTF8Deserializer(use_unicode), UTF8Deserializer(use_unicode))) |
.. note:: Experimental
Read a directory of binary files from HDFS, a local file system
(available on all nodes), or any Hadoop-supported file system URI
as a byte array. Each file is read as a single record and returned
in a key-value pair, where the key is the path of each file, the
value is the content of each file.
.. note:: Small files are preferred, large file is also allowable, but
may cause bad performance. | def binaryFiles(self, path, minPartitions=None):
"""
.. note:: Experimental
Read a directory of binary files from HDFS, a local file system
(available on all nodes), or any Hadoop-supported file system URI
as a byte array. Each file is read as a single record and returned
in a key-value pair, where the key is the path of each file, the
value is the content of each file.
.. note:: Small files are preferred, large file is also allowable, but
may cause bad performance.
"""
minPartitions = minPartitions or self.defaultMinPartitions
return RDD(self._jsc.binaryFiles(path, minPartitions), self,
PairDeserializer(UTF8Deserializer(), NoOpSerializer())) |
.. note:: Experimental
Load data from a flat binary file, assuming each record is a set of numbers
with the specified numerical format (see ByteBuffer), and the number of
bytes per record is constant.
:param path: Directory to the input data files
:param recordLength: The length at which to split the records | def binaryRecords(self, path, recordLength):
"""
.. note:: Experimental
Load data from a flat binary file, assuming each record is a set of numbers
with the specified numerical format (see ByteBuffer), and the number of
bytes per record is constant.
:param path: Directory to the input data files
:param recordLength: The length at which to split the records
"""
return RDD(self._jsc.binaryRecords(path, recordLength), self, NoOpSerializer()) |
Read a Hadoop SequenceFile with arbitrary key and value Writable class from HDFS,
a local file system (available on all nodes), or any Hadoop-supported file system URI.
The mechanism is as follows:
1. A Java RDD is created from the SequenceFile or other InputFormat, and the key
and value Writable classes
2. Serialization is attempted via Pyrolite pickling
3. If this fails, the fallback is to call 'toString' on each key and value
4. C{PickleSerializer} is used to deserialize pickled objects on the Python side
:param path: path to sequncefile
:param keyClass: fully qualified classname of key Writable class
(e.g. "org.apache.hadoop.io.Text")
:param valueClass: fully qualified classname of value Writable class
(e.g. "org.apache.hadoop.io.LongWritable")
:param keyConverter:
:param valueConverter:
:param minSplits: minimum splits in dataset
(default min(2, sc.defaultParallelism))
:param batchSize: The number of Python objects represented as a single
Java object. (default 0, choose batchSize automatically) | def sequenceFile(self, path, keyClass=None, valueClass=None, keyConverter=None,
valueConverter=None, minSplits=None, batchSize=0):
"""
Read a Hadoop SequenceFile with arbitrary key and value Writable class from HDFS,
a local file system (available on all nodes), or any Hadoop-supported file system URI.
The mechanism is as follows:
1. A Java RDD is created from the SequenceFile or other InputFormat, and the key
and value Writable classes
2. Serialization is attempted via Pyrolite pickling
3. If this fails, the fallback is to call 'toString' on each key and value
4. C{PickleSerializer} is used to deserialize pickled objects on the Python side
:param path: path to sequncefile
:param keyClass: fully qualified classname of key Writable class
(e.g. "org.apache.hadoop.io.Text")
:param valueClass: fully qualified classname of value Writable class
(e.g. "org.apache.hadoop.io.LongWritable")
:param keyConverter:
:param valueConverter:
:param minSplits: minimum splits in dataset
(default min(2, sc.defaultParallelism))
:param batchSize: The number of Python objects represented as a single
Java object. (default 0, choose batchSize automatically)
"""
minSplits = minSplits or min(self.defaultParallelism, 2)
jrdd = self._jvm.PythonRDD.sequenceFile(self._jsc, path, keyClass, valueClass,
keyConverter, valueConverter, minSplits, batchSize)
return RDD(jrdd, self) |
Read a 'new API' Hadoop InputFormat with arbitrary key and value class from HDFS,
a local file system (available on all nodes), or any Hadoop-supported file system URI.
The mechanism is the same as for sc.sequenceFile.
A Hadoop configuration can be passed in as a Python dict. This will be converted into a
Configuration in Java
:param path: path to Hadoop file
:param inputFormatClass: fully qualified classname of Hadoop InputFormat
(e.g. "org.apache.hadoop.mapreduce.lib.input.TextInputFormat")
:param keyClass: fully qualified classname of key Writable class
(e.g. "org.apache.hadoop.io.Text")
:param valueClass: fully qualified classname of value Writable class
(e.g. "org.apache.hadoop.io.LongWritable")
:param keyConverter: (None by default)
:param valueConverter: (None by default)
:param conf: Hadoop configuration, passed in as a dict
(None by default)
:param batchSize: The number of Python objects represented as a single
Java object. (default 0, choose batchSize automatically) | def newAPIHadoopFile(self, path, inputFormatClass, keyClass, valueClass, keyConverter=None,
valueConverter=None, conf=None, batchSize=0):
"""
Read a 'new API' Hadoop InputFormat with arbitrary key and value class from HDFS,
a local file system (available on all nodes), or any Hadoop-supported file system URI.
The mechanism is the same as for sc.sequenceFile.
A Hadoop configuration can be passed in as a Python dict. This will be converted into a
Configuration in Java
:param path: path to Hadoop file
:param inputFormatClass: fully qualified classname of Hadoop InputFormat
(e.g. "org.apache.hadoop.mapreduce.lib.input.TextInputFormat")
:param keyClass: fully qualified classname of key Writable class
(e.g. "org.apache.hadoop.io.Text")
:param valueClass: fully qualified classname of value Writable class
(e.g. "org.apache.hadoop.io.LongWritable")
:param keyConverter: (None by default)
:param valueConverter: (None by default)
:param conf: Hadoop configuration, passed in as a dict
(None by default)
:param batchSize: The number of Python objects represented as a single
Java object. (default 0, choose batchSize automatically)
"""
jconf = self._dictToJavaMap(conf)
jrdd = self._jvm.PythonRDD.newAPIHadoopFile(self._jsc, path, inputFormatClass, keyClass,
valueClass, keyConverter, valueConverter,
jconf, batchSize)
return RDD(jrdd, self) |
Build the union of a list of RDDs.
This supports unions() of RDDs with different serialized formats,
although this forces them to be reserialized using the default
serializer:
>>> path = os.path.join(tempdir, "union-text.txt")
>>> with open(path, "w") as testFile:
... _ = testFile.write("Hello")
>>> textFile = sc.textFile(path)
>>> textFile.collect()
[u'Hello']
>>> parallelized = sc.parallelize(["World!"])
>>> sorted(sc.union([textFile, parallelized]).collect())
[u'Hello', 'World!'] | def union(self, rdds):
"""
Build the union of a list of RDDs.
This supports unions() of RDDs with different serialized formats,
although this forces them to be reserialized using the default
serializer:
>>> path = os.path.join(tempdir, "union-text.txt")
>>> with open(path, "w") as testFile:
... _ = testFile.write("Hello")
>>> textFile = sc.textFile(path)
>>> textFile.collect()
[u'Hello']
>>> parallelized = sc.parallelize(["World!"])
>>> sorted(sc.union([textFile, parallelized]).collect())
[u'Hello', 'World!']
"""
first_jrdd_deserializer = rdds[0]._jrdd_deserializer
if any(x._jrdd_deserializer != first_jrdd_deserializer for x in rdds):
rdds = [x._reserialize() for x in rdds]
cls = SparkContext._jvm.org.apache.spark.api.java.JavaRDD
jrdds = SparkContext._gateway.new_array(cls, len(rdds))
for i in range(0, len(rdds)):
jrdds[i] = rdds[i]._jrdd
return RDD(self._jsc.union(jrdds), self, rdds[0]._jrdd_deserializer) |
Create an L{Accumulator} with the given initial value, using a given
L{AccumulatorParam} helper object to define how to add values of the
data type if provided. Default AccumulatorParams are used for integers
and floating-point numbers if you do not provide one. For other types,
a custom AccumulatorParam can be used. | def accumulator(self, value, accum_param=None):
"""
Create an L{Accumulator} with the given initial value, using a given
L{AccumulatorParam} helper object to define how to add values of the
data type if provided. Default AccumulatorParams are used for integers
and floating-point numbers if you do not provide one. For other types,
a custom AccumulatorParam can be used.
"""
if accum_param is None:
if isinstance(value, int):
accum_param = accumulators.INT_ACCUMULATOR_PARAM
elif isinstance(value, float):
accum_param = accumulators.FLOAT_ACCUMULATOR_PARAM
elif isinstance(value, complex):
accum_param = accumulators.COMPLEX_ACCUMULATOR_PARAM
else:
raise TypeError("No default accumulator param for type %s" % type(value))
SparkContext._next_accum_id += 1
return Accumulator(SparkContext._next_accum_id - 1, value, accum_param) |
Add a file to be downloaded with this Spark job on every node.
The C{path} passed can be either a local file, a file in HDFS
(or other Hadoop-supported filesystems), or an HTTP, HTTPS or
FTP URI.
To access the file in Spark jobs, use
L{SparkFiles.get(fileName)<pyspark.files.SparkFiles.get>} with the
filename to find its download location.
A directory can be given if the recursive option is set to True.
Currently directories are only supported for Hadoop-supported filesystems.
.. note:: A path can be added only once. Subsequent additions of the same path are ignored.
>>> from pyspark import SparkFiles
>>> path = os.path.join(tempdir, "test.txt")
>>> with open(path, "w") as testFile:
... _ = testFile.write("100")
>>> sc.addFile(path)
>>> def func(iterator):
... with open(SparkFiles.get("test.txt")) as testFile:
... fileVal = int(testFile.readline())
... return [x * fileVal for x in iterator]
>>> sc.parallelize([1, 2, 3, 4]).mapPartitions(func).collect()
[100, 200, 300, 400] | def addFile(self, path, recursive=False):
"""
Add a file to be downloaded with this Spark job on every node.
The C{path} passed can be either a local file, a file in HDFS
(or other Hadoop-supported filesystems), or an HTTP, HTTPS or
FTP URI.
To access the file in Spark jobs, use
L{SparkFiles.get(fileName)<pyspark.files.SparkFiles.get>} with the
filename to find its download location.
A directory can be given if the recursive option is set to True.
Currently directories are only supported for Hadoop-supported filesystems.
.. note:: A path can be added only once. Subsequent additions of the same path are ignored.
>>> from pyspark import SparkFiles
>>> path = os.path.join(tempdir, "test.txt")
>>> with open(path, "w") as testFile:
... _ = testFile.write("100")
>>> sc.addFile(path)
>>> def func(iterator):
... with open(SparkFiles.get("test.txt")) as testFile:
... fileVal = int(testFile.readline())
... return [x * fileVal for x in iterator]
>>> sc.parallelize([1, 2, 3, 4]).mapPartitions(func).collect()
[100, 200, 300, 400]
"""
self._jsc.sc().addFile(path, recursive) |
Add a .py or .zip dependency for all tasks to be executed on this
SparkContext in the future. The C{path} passed can be either a local
file, a file in HDFS (or other Hadoop-supported filesystems), or an
HTTP, HTTPS or FTP URI.
.. note:: A path can be added only once. Subsequent additions of the same path are ignored. | def addPyFile(self, path):
"""
Add a .py or .zip dependency for all tasks to be executed on this
SparkContext in the future. The C{path} passed can be either a local
file, a file in HDFS (or other Hadoop-supported filesystems), or an
HTTP, HTTPS or FTP URI.
.. note:: A path can be added only once. Subsequent additions of the same path are ignored.
"""
self.addFile(path)
(dirname, filename) = os.path.split(path) # dirname may be directory or HDFS/S3 prefix
if filename[-4:].lower() in self.PACKAGE_EXTENSIONS:
self._python_includes.append(filename)
# for tests in local mode
sys.path.insert(1, os.path.join(SparkFiles.getRootDirectory(), filename))
if sys.version > '3':
import importlib
importlib.invalidate_caches() |
Returns a Java StorageLevel based on a pyspark.StorageLevel. | def _getJavaStorageLevel(self, storageLevel):
"""
Returns a Java StorageLevel based on a pyspark.StorageLevel.
"""
if not isinstance(storageLevel, StorageLevel):
raise Exception("storageLevel must be of type pyspark.StorageLevel")
newStorageLevel = self._jvm.org.apache.spark.storage.StorageLevel
return newStorageLevel(storageLevel.useDisk,
storageLevel.useMemory,
storageLevel.useOffHeap,
storageLevel.deserialized,
storageLevel.replication) |
Assigns a group ID to all the jobs started by this thread until the group ID is set to a
different value or cleared.
Often, a unit of execution in an application consists of multiple Spark actions or jobs.
Application programmers can use this method to group all those jobs together and give a
group description. Once set, the Spark web UI will associate such jobs with this group.
The application can use L{SparkContext.cancelJobGroup} to cancel all
running jobs in this group.
>>> import threading
>>> from time import sleep
>>> result = "Not Set"
>>> lock = threading.Lock()
>>> def map_func(x):
... sleep(100)
... raise Exception("Task should have been cancelled")
>>> def start_job(x):
... global result
... try:
... sc.setJobGroup("job_to_cancel", "some description")
... result = sc.parallelize(range(x)).map(map_func).collect()
... except Exception as e:
... result = "Cancelled"
... lock.release()
>>> def stop_job():
... sleep(5)
... sc.cancelJobGroup("job_to_cancel")
>>> suppress = lock.acquire()
>>> suppress = threading.Thread(target=start_job, args=(10,)).start()
>>> suppress = threading.Thread(target=stop_job).start()
>>> suppress = lock.acquire()
>>> print(result)
Cancelled
If interruptOnCancel is set to true for the job group, then job cancellation will result
in Thread.interrupt() being called on the job's executor threads. This is useful to help
ensure that the tasks are actually stopped in a timely manner, but is off by default due
to HDFS-1208, where HDFS may respond to Thread.interrupt() by marking nodes as dead. | def setJobGroup(self, groupId, description, interruptOnCancel=False):
"""
Assigns a group ID to all the jobs started by this thread until the group ID is set to a
different value or cleared.
Often, a unit of execution in an application consists of multiple Spark actions or jobs.
Application programmers can use this method to group all those jobs together and give a
group description. Once set, the Spark web UI will associate such jobs with this group.
The application can use L{SparkContext.cancelJobGroup} to cancel all
running jobs in this group.
>>> import threading
>>> from time import sleep
>>> result = "Not Set"
>>> lock = threading.Lock()
>>> def map_func(x):
... sleep(100)
... raise Exception("Task should have been cancelled")
>>> def start_job(x):
... global result
... try:
... sc.setJobGroup("job_to_cancel", "some description")
... result = sc.parallelize(range(x)).map(map_func).collect()
... except Exception as e:
... result = "Cancelled"
... lock.release()
>>> def stop_job():
... sleep(5)
... sc.cancelJobGroup("job_to_cancel")
>>> suppress = lock.acquire()
>>> suppress = threading.Thread(target=start_job, args=(10,)).start()
>>> suppress = threading.Thread(target=stop_job).start()
>>> suppress = lock.acquire()
>>> print(result)
Cancelled
If interruptOnCancel is set to true for the job group, then job cancellation will result
in Thread.interrupt() being called on the job's executor threads. This is useful to help
ensure that the tasks are actually stopped in a timely manner, but is off by default due
to HDFS-1208, where HDFS may respond to Thread.interrupt() by marking nodes as dead.
"""
self._jsc.setJobGroup(groupId, description, interruptOnCancel) |
Executes the given partitionFunc on the specified set of partitions,
returning the result as an array of elements.
If 'partitions' is not specified, this will run over all partitions.
>>> myRDD = sc.parallelize(range(6), 3)
>>> sc.runJob(myRDD, lambda part: [x * x for x in part])
[0, 1, 4, 9, 16, 25]
>>> myRDD = sc.parallelize(range(6), 3)
>>> sc.runJob(myRDD, lambda part: [x * x for x in part], [0, 2], True)
[0, 1, 16, 25] | def runJob(self, rdd, partitionFunc, partitions=None, allowLocal=False):
"""
Executes the given partitionFunc on the specified set of partitions,
returning the result as an array of elements.
If 'partitions' is not specified, this will run over all partitions.
>>> myRDD = sc.parallelize(range(6), 3)
>>> sc.runJob(myRDD, lambda part: [x * x for x in part])
[0, 1, 4, 9, 16, 25]
>>> myRDD = sc.parallelize(range(6), 3)
>>> sc.runJob(myRDD, lambda part: [x * x for x in part], [0, 2], True)
[0, 1, 16, 25]
"""
if partitions is None:
partitions = range(rdd._jrdd.partitions().size())
# Implementation note: This is implemented as a mapPartitions followed
# by runJob() in order to avoid having to pass a Python lambda into
# SparkContext#runJob.
mappedRDD = rdd.mapPartitions(partitionFunc)
sock_info = self._jvm.PythonRDD.runJob(self._jsc.sc(), mappedRDD._jrdd, partitions)
return list(_load_from_socket(sock_info, mappedRDD._jrdd_deserializer)) |
Dump the profile stats into directory `path` | def dump_profiles(self, path):
""" Dump the profile stats into directory `path`
"""
if self.profiler_collector is not None:
self.profiler_collector.dump_profiles(path)
else:
raise RuntimeError("'spark.python.profile' configuration must be set "
"to 'true' to enable Python profile.") |
Train a matrix factorization model given an RDD of ratings by users
for a subset of products. The ratings matrix is approximated as the
product of two lower-rank matrices of a given rank (number of
features). To solve for these features, ALS is run iteratively with
a configurable level of parallelism.
:param ratings:
RDD of `Rating` or (userID, productID, rating) tuple.
:param rank:
Number of features to use (also referred to as the number of latent factors).
:param iterations:
Number of iterations of ALS.
(default: 5)
:param lambda_:
Regularization parameter.
(default: 0.01)
:param blocks:
Number of blocks used to parallelize the computation. A value
of -1 will use an auto-configured number of blocks.
(default: -1)
:param nonnegative:
A value of True will solve least-squares with nonnegativity
constraints.
(default: False)
:param seed:
Random seed for initial matrix factorization model. A value
of None will use system time as the seed.
(default: None) | def train(cls, ratings, rank, iterations=5, lambda_=0.01, blocks=-1, nonnegative=False,
seed=None):
"""
Train a matrix factorization model given an RDD of ratings by users
for a subset of products. The ratings matrix is approximated as the
product of two lower-rank matrices of a given rank (number of
features). To solve for these features, ALS is run iteratively with
a configurable level of parallelism.
:param ratings:
RDD of `Rating` or (userID, productID, rating) tuple.
:param rank:
Number of features to use (also referred to as the number of latent factors).
:param iterations:
Number of iterations of ALS.
(default: 5)
:param lambda_:
Regularization parameter.
(default: 0.01)
:param blocks:
Number of blocks used to parallelize the computation. A value
of -1 will use an auto-configured number of blocks.
(default: -1)
:param nonnegative:
A value of True will solve least-squares with nonnegativity
constraints.
(default: False)
:param seed:
Random seed for initial matrix factorization model. A value
of None will use system time as the seed.
(default: None)
"""
model = callMLlibFunc("trainALSModel", cls._prepare(ratings), rank, iterations,
lambda_, blocks, nonnegative, seed)
return MatrixFactorizationModel(model) |
Computes an FP-Growth model that contains frequent itemsets.
:param data:
The input data set, each element contains a transaction.
:param minSupport:
The minimal support level.
(default: 0.3)
:param numPartitions:
The number of partitions used by parallel FP-growth. A value
of -1 will use the same number as input data.
(default: -1) | def train(cls, data, minSupport=0.3, numPartitions=-1):
"""
Computes an FP-Growth model that contains frequent itemsets.
:param data:
The input data set, each element contains a transaction.
:param minSupport:
The minimal support level.
(default: 0.3)
:param numPartitions:
The number of partitions used by parallel FP-growth. A value
of -1 will use the same number as input data.
(default: -1)
"""
model = callMLlibFunc("trainFPGrowthModel", data, float(minSupport), int(numPartitions))
return FPGrowthModel(model) |
Finds the complete set of frequent sequential patterns in the
input sequences of itemsets.
:param data:
The input data set, each element contains a sequence of
itemsets.
:param minSupport:
The minimal support level of the sequential pattern, any
pattern that appears more than (minSupport *
size-of-the-dataset) times will be output.
(default: 0.1)
:param maxPatternLength:
The maximal length of the sequential pattern, any pattern
that appears less than maxPatternLength will be output.
(default: 10)
:param maxLocalProjDBSize:
The maximum number of items (including delimiters used in the
internal storage format) allowed in a projected database before
local processing. If a projected database exceeds this size,
another iteration of distributed prefix growth is run.
(default: 32000000) | def train(cls, data, minSupport=0.1, maxPatternLength=10, maxLocalProjDBSize=32000000):
"""
Finds the complete set of frequent sequential patterns in the
input sequences of itemsets.
:param data:
The input data set, each element contains a sequence of
itemsets.
:param minSupport:
The minimal support level of the sequential pattern, any
pattern that appears more than (minSupport *
size-of-the-dataset) times will be output.
(default: 0.1)
:param maxPatternLength:
The maximal length of the sequential pattern, any pattern
that appears less than maxPatternLength will be output.
(default: 10)
:param maxLocalProjDBSize:
The maximum number of items (including delimiters used in the
internal storage format) allowed in a projected database before
local processing. If a projected database exceeds this size,
another iteration of distributed prefix growth is run.
(default: 32000000)
"""
model = callMLlibFunc("trainPrefixSpanModel",
data, minSupport, maxPatternLength, maxLocalProjDBSize)
return PrefixSpanModel(model) |
Set sample points from the population. Should be a RDD | def setSample(self, sample):
"""Set sample points from the population. Should be a RDD"""
if not isinstance(sample, RDD):
raise TypeError("samples should be a RDD, received %s" % type(sample))
self._sample = sample |
Estimate the probability density at points | def estimate(self, points):
"""Estimate the probability density at points"""
points = list(points)
densities = callMLlibFunc(
"estimateKernelDensity", self._sample, self._bandwidth, points)
return np.asarray(densities) |
Start a TCP server to receive accumulator updates in a daemon thread, and returns it | def _start_update_server(auth_token):
"""Start a TCP server to receive accumulator updates in a daemon thread, and returns it"""
server = AccumulatorServer(("localhost", 0), _UpdateRequestHandler, auth_token)
thread = threading.Thread(target=server.serve_forever)
thread.daemon = True
thread.start()
return server |
Adds a term to this accumulator's value | def add(self, term):
"""Adds a term to this accumulator's value"""
self._value = self.accum_param.addInPlace(self._value, term) |
Compute aggregates and returns the result as a :class:`DataFrame`.
The available aggregate functions can be:
1. built-in aggregation functions, such as `avg`, `max`, `min`, `sum`, `count`
2. group aggregate pandas UDFs, created with :func:`pyspark.sql.functions.pandas_udf`
.. note:: There is no partial aggregation with group aggregate UDFs, i.e.,
a full shuffle is required. Also, all the data of a group will be loaded into
memory, so the user should be aware of the potential OOM risk if data is skewed
and certain groups are too large to fit in memory.
.. seealso:: :func:`pyspark.sql.functions.pandas_udf`
If ``exprs`` is a single :class:`dict` mapping from string to string, then the key
is the column to perform aggregation on, and the value is the aggregate function.
Alternatively, ``exprs`` can also be a list of aggregate :class:`Column` expressions.
.. note:: Built-in aggregation functions and group aggregate pandas UDFs cannot be mixed
in a single call to this function.
:param exprs: a dict mapping from column name (string) to aggregate functions (string),
or a list of :class:`Column`.
>>> gdf = df.groupBy(df.name)
>>> sorted(gdf.agg({"*": "count"}).collect())
[Row(name=u'Alice', count(1)=1), Row(name=u'Bob', count(1)=1)]
>>> from pyspark.sql import functions as F
>>> sorted(gdf.agg(F.min(df.age)).collect())
[Row(name=u'Alice', min(age)=2), Row(name=u'Bob', min(age)=5)]
>>> from pyspark.sql.functions import pandas_udf, PandasUDFType
>>> @pandas_udf('int', PandasUDFType.GROUPED_AGG) # doctest: +SKIP
... def min_udf(v):
... return v.min()
>>> sorted(gdf.agg(min_udf(df.age)).collect()) # doctest: +SKIP
[Row(name=u'Alice', min_udf(age)=2), Row(name=u'Bob', min_udf(age)=5)] | def agg(self, *exprs):
"""Compute aggregates and returns the result as a :class:`DataFrame`.
The available aggregate functions can be:
1. built-in aggregation functions, such as `avg`, `max`, `min`, `sum`, `count`
2. group aggregate pandas UDFs, created with :func:`pyspark.sql.functions.pandas_udf`
.. note:: There is no partial aggregation with group aggregate UDFs, i.e.,
a full shuffle is required. Also, all the data of a group will be loaded into
memory, so the user should be aware of the potential OOM risk if data is skewed
and certain groups are too large to fit in memory.
.. seealso:: :func:`pyspark.sql.functions.pandas_udf`
If ``exprs`` is a single :class:`dict` mapping from string to string, then the key
is the column to perform aggregation on, and the value is the aggregate function.
Alternatively, ``exprs`` can also be a list of aggregate :class:`Column` expressions.
.. note:: Built-in aggregation functions and group aggregate pandas UDFs cannot be mixed
in a single call to this function.
:param exprs: a dict mapping from column name (string) to aggregate functions (string),
or a list of :class:`Column`.
>>> gdf = df.groupBy(df.name)
>>> sorted(gdf.agg({"*": "count"}).collect())
[Row(name=u'Alice', count(1)=1), Row(name=u'Bob', count(1)=1)]
>>> from pyspark.sql import functions as F
>>> sorted(gdf.agg(F.min(df.age)).collect())
[Row(name=u'Alice', min(age)=2), Row(name=u'Bob', min(age)=5)]
>>> from pyspark.sql.functions import pandas_udf, PandasUDFType
>>> @pandas_udf('int', PandasUDFType.GROUPED_AGG) # doctest: +SKIP
... def min_udf(v):
... return v.min()
>>> sorted(gdf.agg(min_udf(df.age)).collect()) # doctest: +SKIP
[Row(name=u'Alice', min_udf(age)=2), Row(name=u'Bob', min_udf(age)=5)]
"""
assert exprs, "exprs should not be empty"
if len(exprs) == 1 and isinstance(exprs[0], dict):
jdf = self._jgd.agg(exprs[0])
else:
# Columns
assert all(isinstance(c, Column) for c in exprs), "all exprs should be Column"
jdf = self._jgd.agg(exprs[0]._jc,
_to_seq(self.sql_ctx._sc, [c._jc for c in exprs[1:]]))
return DataFrame(jdf, self.sql_ctx) |
Pivots a column of the current :class:`DataFrame` and perform the specified aggregation.
There are two versions of pivot function: one that requires the caller to specify the list
of distinct values to pivot on, and one that does not. The latter is more concise but less
efficient, because Spark needs to first compute the list of distinct values internally.
:param pivot_col: Name of the column to pivot.
:param values: List of values that will be translated to columns in the output DataFrame.
# Compute the sum of earnings for each year by course with each course as a separate column
>>> df4.groupBy("year").pivot("course", ["dotNET", "Java"]).sum("earnings").collect()
[Row(year=2012, dotNET=15000, Java=20000), Row(year=2013, dotNET=48000, Java=30000)]
# Or without specifying column values (less efficient)
>>> df4.groupBy("year").pivot("course").sum("earnings").collect()
[Row(year=2012, Java=20000, dotNET=15000), Row(year=2013, Java=30000, dotNET=48000)]
>>> df5.groupBy("sales.year").pivot("sales.course").sum("sales.earnings").collect()
[Row(year=2012, Java=20000, dotNET=15000), Row(year=2013, Java=30000, dotNET=48000)] | def pivot(self, pivot_col, values=None):
"""
Pivots a column of the current :class:`DataFrame` and perform the specified aggregation.
There are two versions of pivot function: one that requires the caller to specify the list
of distinct values to pivot on, and one that does not. The latter is more concise but less
efficient, because Spark needs to first compute the list of distinct values internally.
:param pivot_col: Name of the column to pivot.
:param values: List of values that will be translated to columns in the output DataFrame.
# Compute the sum of earnings for each year by course with each course as a separate column
>>> df4.groupBy("year").pivot("course", ["dotNET", "Java"]).sum("earnings").collect()
[Row(year=2012, dotNET=15000, Java=20000), Row(year=2013, dotNET=48000, Java=30000)]
# Or without specifying column values (less efficient)
>>> df4.groupBy("year").pivot("course").sum("earnings").collect()
[Row(year=2012, Java=20000, dotNET=15000), Row(year=2013, Java=30000, dotNET=48000)]
>>> df5.groupBy("sales.year").pivot("sales.course").sum("sales.earnings").collect()
[Row(year=2012, Java=20000, dotNET=15000), Row(year=2013, Java=30000, dotNET=48000)]
"""
if values is None:
jgd = self._jgd.pivot(pivot_col)
else:
jgd = self._jgd.pivot(pivot_col, values)
return GroupedData(jgd, self._df) |
Maps each group of the current :class:`DataFrame` using a pandas udf and returns the result
as a `DataFrame`.
The user-defined function should take a `pandas.DataFrame` and return another
`pandas.DataFrame`. For each group, all columns are passed together as a `pandas.DataFrame`
to the user-function and the returned `pandas.DataFrame` are combined as a
:class:`DataFrame`.
The returned `pandas.DataFrame` can be of arbitrary length and its schema must match the
returnType of the pandas udf.
.. note:: This function requires a full shuffle. all the data of a group will be loaded
into memory, so the user should be aware of the potential OOM risk if data is skewed
and certain groups are too large to fit in memory.
.. note:: Experimental
:param udf: a grouped map user-defined function returned by
:func:`pyspark.sql.functions.pandas_udf`.
>>> from pyspark.sql.functions import pandas_udf, PandasUDFType
>>> df = spark.createDataFrame(
... [(1, 1.0), (1, 2.0), (2, 3.0), (2, 5.0), (2, 10.0)],
... ("id", "v"))
>>> @pandas_udf("id long, v double", PandasUDFType.GROUPED_MAP) # doctest: +SKIP
... def normalize(pdf):
... v = pdf.v
... return pdf.assign(v=(v - v.mean()) / v.std())
>>> df.groupby("id").apply(normalize).show() # doctest: +SKIP
+---+-------------------+
| id| v|
+---+-------------------+
| 1|-0.7071067811865475|
| 1| 0.7071067811865475|
| 2|-0.8320502943378437|
| 2|-0.2773500981126146|
| 2| 1.1094003924504583|
+---+-------------------+
.. seealso:: :meth:`pyspark.sql.functions.pandas_udf` | def apply(self, udf):
"""
Maps each group of the current :class:`DataFrame` using a pandas udf and returns the result
as a `DataFrame`.
The user-defined function should take a `pandas.DataFrame` and return another
`pandas.DataFrame`. For each group, all columns are passed together as a `pandas.DataFrame`
to the user-function and the returned `pandas.DataFrame` are combined as a
:class:`DataFrame`.
The returned `pandas.DataFrame` can be of arbitrary length and its schema must match the
returnType of the pandas udf.
.. note:: This function requires a full shuffle. all the data of a group will be loaded
into memory, so the user should be aware of the potential OOM risk if data is skewed
and certain groups are too large to fit in memory.
.. note:: Experimental
:param udf: a grouped map user-defined function returned by
:func:`pyspark.sql.functions.pandas_udf`.
>>> from pyspark.sql.functions import pandas_udf, PandasUDFType
>>> df = spark.createDataFrame(
... [(1, 1.0), (1, 2.0), (2, 3.0), (2, 5.0), (2, 10.0)],
... ("id", "v"))
>>> @pandas_udf("id long, v double", PandasUDFType.GROUPED_MAP) # doctest: +SKIP
... def normalize(pdf):
... v = pdf.v
... return pdf.assign(v=(v - v.mean()) / v.std())
>>> df.groupby("id").apply(normalize).show() # doctest: +SKIP
+---+-------------------+
| id| v|
+---+-------------------+
| 1|-0.7071067811865475|
| 1| 0.7071067811865475|
| 2|-0.8320502943378437|
| 2|-0.2773500981126146|
| 2| 1.1094003924504583|
+---+-------------------+
.. seealso:: :meth:`pyspark.sql.functions.pandas_udf`
"""
# Columns are special because hasattr always return True
if isinstance(udf, Column) or not hasattr(udf, 'func') \
or udf.evalType != PythonEvalType.SQL_GROUPED_MAP_PANDAS_UDF:
raise ValueError("Invalid udf: the udf argument must be a pandas_udf of type "
"GROUPED_MAP.")
df = self._df
udf_column = udf(*[df[col] for col in df.columns])
jdf = self._jgd.flatMapGroupsInPandas(udf_column._jc.expr())
return DataFrame(jdf, self.sql_ctx) |
Creates a :class:`WindowSpec` with the partitioning defined. | def partitionBy(*cols):
"""
Creates a :class:`WindowSpec` with the partitioning defined.
"""
sc = SparkContext._active_spark_context
jspec = sc._jvm.org.apache.spark.sql.expressions.Window.partitionBy(_to_java_cols(cols))
return WindowSpec(jspec) |
Creates a :class:`WindowSpec` with the frame boundaries defined,
from `start` (inclusive) to `end` (inclusive).
Both `start` and `end` are relative positions from the current row.
For example, "0" means "current row", while "-1" means the row before
the current row, and "5" means the fifth row after the current row.
We recommend users use ``Window.unboundedPreceding``, ``Window.unboundedFollowing``,
and ``Window.currentRow`` to specify special boundary values, rather than using integral
values directly.
A row based boundary is based on the position of the row within the partition.
An offset indicates the number of rows above or below the current row, the frame for the
current row starts or ends. For instance, given a row based sliding frame with a lower bound
offset of -1 and a upper bound offset of +2. The frame for row with index 5 would range from
index 4 to index 6.
>>> from pyspark.sql import Window
>>> from pyspark.sql import functions as func
>>> from pyspark.sql import SQLContext
>>> sc = SparkContext.getOrCreate()
>>> sqlContext = SQLContext(sc)
>>> tup = [(1, "a"), (1, "a"), (2, "a"), (1, "b"), (2, "b"), (3, "b")]
>>> df = sqlContext.createDataFrame(tup, ["id", "category"])
>>> window = Window.partitionBy("category").orderBy("id").rowsBetween(Window.currentRow, 1)
>>> df.withColumn("sum", func.sum("id").over(window)).show()
+---+--------+---+
| id|category|sum|
+---+--------+---+
| 1| b| 3|
| 2| b| 5|
| 3| b| 3|
| 1| a| 2|
| 1| a| 3|
| 2| a| 2|
+---+--------+---+
:param start: boundary start, inclusive.
The frame is unbounded if this is ``Window.unboundedPreceding``, or
any value less than or equal to -9223372036854775808.
:param end: boundary end, inclusive.
The frame is unbounded if this is ``Window.unboundedFollowing``, or
any value greater than or equal to 9223372036854775807. | def rowsBetween(start, end):
"""
Creates a :class:`WindowSpec` with the frame boundaries defined,
from `start` (inclusive) to `end` (inclusive).
Both `start` and `end` are relative positions from the current row.
For example, "0" means "current row", while "-1" means the row before
the current row, and "5" means the fifth row after the current row.
We recommend users use ``Window.unboundedPreceding``, ``Window.unboundedFollowing``,
and ``Window.currentRow`` to specify special boundary values, rather than using integral
values directly.
A row based boundary is based on the position of the row within the partition.
An offset indicates the number of rows above or below the current row, the frame for the
current row starts or ends. For instance, given a row based sliding frame with a lower bound
offset of -1 and a upper bound offset of +2. The frame for row with index 5 would range from
index 4 to index 6.
>>> from pyspark.sql import Window
>>> from pyspark.sql import functions as func
>>> from pyspark.sql import SQLContext
>>> sc = SparkContext.getOrCreate()
>>> sqlContext = SQLContext(sc)
>>> tup = [(1, "a"), (1, "a"), (2, "a"), (1, "b"), (2, "b"), (3, "b")]
>>> df = sqlContext.createDataFrame(tup, ["id", "category"])
>>> window = Window.partitionBy("category").orderBy("id").rowsBetween(Window.currentRow, 1)
>>> df.withColumn("sum", func.sum("id").over(window)).show()
+---+--------+---+
| id|category|sum|
+---+--------+---+
| 1| b| 3|
| 2| b| 5|
| 3| b| 3|
| 1| a| 2|
| 1| a| 3|
| 2| a| 2|
+---+--------+---+
:param start: boundary start, inclusive.
The frame is unbounded if this is ``Window.unboundedPreceding``, or
any value less than or equal to -9223372036854775808.
:param end: boundary end, inclusive.
The frame is unbounded if this is ``Window.unboundedFollowing``, or
any value greater than or equal to 9223372036854775807.
"""
if start <= Window._PRECEDING_THRESHOLD:
start = Window.unboundedPreceding
if end >= Window._FOLLOWING_THRESHOLD:
end = Window.unboundedFollowing
sc = SparkContext._active_spark_context
jspec = sc._jvm.org.apache.spark.sql.expressions.Window.rowsBetween(start, end)
return WindowSpec(jspec) |
Defines the frame boundaries, from `start` (inclusive) to `end` (inclusive).
Both `start` and `end` are relative positions from the current row.
For example, "0" means "current row", while "-1" means the row before
the current row, and "5" means the fifth row after the current row.
We recommend users use ``Window.unboundedPreceding``, ``Window.unboundedFollowing``,
and ``Window.currentRow`` to specify special boundary values, rather than using integral
values directly.
:param start: boundary start, inclusive.
The frame is unbounded if this is ``Window.unboundedPreceding``, or
any value less than or equal to max(-sys.maxsize, -9223372036854775808).
:param end: boundary end, inclusive.
The frame is unbounded if this is ``Window.unboundedFollowing``, or
any value greater than or equal to min(sys.maxsize, 9223372036854775807). | def rowsBetween(self, start, end):
"""
Defines the frame boundaries, from `start` (inclusive) to `end` (inclusive).
Both `start` and `end` are relative positions from the current row.
For example, "0" means "current row", while "-1" means the row before
the current row, and "5" means the fifth row after the current row.
We recommend users use ``Window.unboundedPreceding``, ``Window.unboundedFollowing``,
and ``Window.currentRow`` to specify special boundary values, rather than using integral
values directly.
:param start: boundary start, inclusive.
The frame is unbounded if this is ``Window.unboundedPreceding``, or
any value less than or equal to max(-sys.maxsize, -9223372036854775808).
:param end: boundary end, inclusive.
The frame is unbounded if this is ``Window.unboundedFollowing``, or
any value greater than or equal to min(sys.maxsize, 9223372036854775807).
"""
if start <= Window._PRECEDING_THRESHOLD:
start = Window.unboundedPreceding
if end >= Window._FOLLOWING_THRESHOLD:
end = Window.unboundedFollowing
return WindowSpec(self._jspec.rowsBetween(start, end)) |
Generates an RDD comprised of i.i.d. samples from the
uniform distribution U(0.0, 1.0).
To transform the distribution in the generated RDD from U(0.0, 1.0)
to U(a, b), use
C{RandomRDDs.uniformRDD(sc, n, p, seed)\
.map(lambda v: a + (b - a) * v)}
:param sc: SparkContext used to create the RDD.
:param size: Size of the RDD.
:param numPartitions: Number of partitions in the RDD (default: `sc.defaultParallelism`).
:param seed: Random seed (default: a random long integer).
:return: RDD of float comprised of i.i.d. samples ~ `U(0.0, 1.0)`.
>>> x = RandomRDDs.uniformRDD(sc, 100).collect()
>>> len(x)
100
>>> max(x) <= 1.0 and min(x) >= 0.0
True
>>> RandomRDDs.uniformRDD(sc, 100, 4).getNumPartitions()
4
>>> parts = RandomRDDs.uniformRDD(sc, 100, seed=4).getNumPartitions()
>>> parts == sc.defaultParallelism
True | def uniformRDD(sc, size, numPartitions=None, seed=None):
"""
Generates an RDD comprised of i.i.d. samples from the
uniform distribution U(0.0, 1.0).
To transform the distribution in the generated RDD from U(0.0, 1.0)
to U(a, b), use
C{RandomRDDs.uniformRDD(sc, n, p, seed)\
.map(lambda v: a + (b - a) * v)}
:param sc: SparkContext used to create the RDD.
:param size: Size of the RDD.
:param numPartitions: Number of partitions in the RDD (default: `sc.defaultParallelism`).
:param seed: Random seed (default: a random long integer).
:return: RDD of float comprised of i.i.d. samples ~ `U(0.0, 1.0)`.
>>> x = RandomRDDs.uniformRDD(sc, 100).collect()
>>> len(x)
100
>>> max(x) <= 1.0 and min(x) >= 0.0
True
>>> RandomRDDs.uniformRDD(sc, 100, 4).getNumPartitions()
4
>>> parts = RandomRDDs.uniformRDD(sc, 100, seed=4).getNumPartitions()
>>> parts == sc.defaultParallelism
True
"""
return callMLlibFunc("uniformRDD", sc._jsc, size, numPartitions, seed) |
Generates an RDD comprised of i.i.d. samples from the standard normal
distribution.
To transform the distribution in the generated RDD from standard normal
to some other normal N(mean, sigma^2), use
C{RandomRDDs.normal(sc, n, p, seed)\
.map(lambda v: mean + sigma * v)}
:param sc: SparkContext used to create the RDD.
:param size: Size of the RDD.
:param numPartitions: Number of partitions in the RDD (default: `sc.defaultParallelism`).
:param seed: Random seed (default: a random long integer).
:return: RDD of float comprised of i.i.d. samples ~ N(0.0, 1.0).
>>> x = RandomRDDs.normalRDD(sc, 1000, seed=1)
>>> stats = x.stats()
>>> stats.count()
1000
>>> abs(stats.mean() - 0.0) < 0.1
True
>>> abs(stats.stdev() - 1.0) < 0.1
True | def normalRDD(sc, size, numPartitions=None, seed=None):
"""
Generates an RDD comprised of i.i.d. samples from the standard normal
distribution.
To transform the distribution in the generated RDD from standard normal
to some other normal N(mean, sigma^2), use
C{RandomRDDs.normal(sc, n, p, seed)\
.map(lambda v: mean + sigma * v)}
:param sc: SparkContext used to create the RDD.
:param size: Size of the RDD.
:param numPartitions: Number of partitions in the RDD (default: `sc.defaultParallelism`).
:param seed: Random seed (default: a random long integer).
:return: RDD of float comprised of i.i.d. samples ~ N(0.0, 1.0).
>>> x = RandomRDDs.normalRDD(sc, 1000, seed=1)
>>> stats = x.stats()
>>> stats.count()
1000
>>> abs(stats.mean() - 0.0) < 0.1
True
>>> abs(stats.stdev() - 1.0) < 0.1
True
"""
return callMLlibFunc("normalRDD", sc._jsc, size, numPartitions, seed) |
Generates an RDD comprised of i.i.d. samples from the log normal
distribution with the input mean and standard distribution.
:param sc: SparkContext used to create the RDD.
:param mean: mean for the log Normal distribution
:param std: std for the log Normal distribution
:param size: Size of the RDD.
:param numPartitions: Number of partitions in the RDD (default: `sc.defaultParallelism`).
:param seed: Random seed (default: a random long integer).
:return: RDD of float comprised of i.i.d. samples ~ log N(mean, std).
>>> from math import sqrt, exp
>>> mean = 0.0
>>> std = 1.0
>>> expMean = exp(mean + 0.5 * std * std)
>>> expStd = sqrt((exp(std * std) - 1.0) * exp(2.0 * mean + std * std))
>>> x = RandomRDDs.logNormalRDD(sc, mean, std, 1000, seed=2)
>>> stats = x.stats()
>>> stats.count()
1000
>>> abs(stats.mean() - expMean) < 0.5
True
>>> from math import sqrt
>>> abs(stats.stdev() - expStd) < 0.5
True | def logNormalRDD(sc, mean, std, size, numPartitions=None, seed=None):
"""
Generates an RDD comprised of i.i.d. samples from the log normal
distribution with the input mean and standard distribution.
:param sc: SparkContext used to create the RDD.
:param mean: mean for the log Normal distribution
:param std: std for the log Normal distribution
:param size: Size of the RDD.
:param numPartitions: Number of partitions in the RDD (default: `sc.defaultParallelism`).
:param seed: Random seed (default: a random long integer).
:return: RDD of float comprised of i.i.d. samples ~ log N(mean, std).
>>> from math import sqrt, exp
>>> mean = 0.0
>>> std = 1.0
>>> expMean = exp(mean + 0.5 * std * std)
>>> expStd = sqrt((exp(std * std) - 1.0) * exp(2.0 * mean + std * std))
>>> x = RandomRDDs.logNormalRDD(sc, mean, std, 1000, seed=2)
>>> stats = x.stats()
>>> stats.count()
1000
>>> abs(stats.mean() - expMean) < 0.5
True
>>> from math import sqrt
>>> abs(stats.stdev() - expStd) < 0.5
True
"""
return callMLlibFunc("logNormalRDD", sc._jsc, float(mean), float(std),
size, numPartitions, seed) |
Generates an RDD comprised of i.i.d. samples from the Exponential
distribution with the input mean.
:param sc: SparkContext used to create the RDD.
:param mean: Mean, or 1 / lambda, for the Exponential distribution.
:param size: Size of the RDD.
:param numPartitions: Number of partitions in the RDD (default: `sc.defaultParallelism`).
:param seed: Random seed (default: a random long integer).
:return: RDD of float comprised of i.i.d. samples ~ Exp(mean).
>>> mean = 2.0
>>> x = RandomRDDs.exponentialRDD(sc, mean, 1000, seed=2)
>>> stats = x.stats()
>>> stats.count()
1000
>>> abs(stats.mean() - mean) < 0.5
True
>>> from math import sqrt
>>> abs(stats.stdev() - sqrt(mean)) < 0.5
True | def exponentialRDD(sc, mean, size, numPartitions=None, seed=None):
"""
Generates an RDD comprised of i.i.d. samples from the Exponential
distribution with the input mean.
:param sc: SparkContext used to create the RDD.
:param mean: Mean, or 1 / lambda, for the Exponential distribution.
:param size: Size of the RDD.
:param numPartitions: Number of partitions in the RDD (default: `sc.defaultParallelism`).
:param seed: Random seed (default: a random long integer).
:return: RDD of float comprised of i.i.d. samples ~ Exp(mean).
>>> mean = 2.0
>>> x = RandomRDDs.exponentialRDD(sc, mean, 1000, seed=2)
>>> stats = x.stats()
>>> stats.count()
1000
>>> abs(stats.mean() - mean) < 0.5
True
>>> from math import sqrt
>>> abs(stats.stdev() - sqrt(mean)) < 0.5
True
"""
return callMLlibFunc("exponentialRDD", sc._jsc, float(mean), size, numPartitions, seed) |
Generates an RDD comprised of i.i.d. samples from the Gamma
distribution with the input shape and scale.
:param sc: SparkContext used to create the RDD.
:param shape: shape (> 0) parameter for the Gamma distribution
:param scale: scale (> 0) parameter for the Gamma distribution
:param size: Size of the RDD.
:param numPartitions: Number of partitions in the RDD (default: `sc.defaultParallelism`).
:param seed: Random seed (default: a random long integer).
:return: RDD of float comprised of i.i.d. samples ~ Gamma(shape, scale).
>>> from math import sqrt
>>> shape = 1.0
>>> scale = 2.0
>>> expMean = shape * scale
>>> expStd = sqrt(shape * scale * scale)
>>> x = RandomRDDs.gammaRDD(sc, shape, scale, 1000, seed=2)
>>> stats = x.stats()
>>> stats.count()
1000
>>> abs(stats.mean() - expMean) < 0.5
True
>>> abs(stats.stdev() - expStd) < 0.5
True | def gammaRDD(sc, shape, scale, size, numPartitions=None, seed=None):
"""
Generates an RDD comprised of i.i.d. samples from the Gamma
distribution with the input shape and scale.
:param sc: SparkContext used to create the RDD.
:param shape: shape (> 0) parameter for the Gamma distribution
:param scale: scale (> 0) parameter for the Gamma distribution
:param size: Size of the RDD.
:param numPartitions: Number of partitions in the RDD (default: `sc.defaultParallelism`).
:param seed: Random seed (default: a random long integer).
:return: RDD of float comprised of i.i.d. samples ~ Gamma(shape, scale).
>>> from math import sqrt
>>> shape = 1.0
>>> scale = 2.0
>>> expMean = shape * scale
>>> expStd = sqrt(shape * scale * scale)
>>> x = RandomRDDs.gammaRDD(sc, shape, scale, 1000, seed=2)
>>> stats = x.stats()
>>> stats.count()
1000
>>> abs(stats.mean() - expMean) < 0.5
True
>>> abs(stats.stdev() - expStd) < 0.5
True
"""
return callMLlibFunc("gammaRDD", sc._jsc, float(shape),
float(scale), size, numPartitions, seed) |
Generates an RDD comprised of vectors containing i.i.d. samples drawn
from the uniform distribution U(0.0, 1.0).
:param sc: SparkContext used to create the RDD.
:param numRows: Number of Vectors in the RDD.
:param numCols: Number of elements in each Vector.
:param numPartitions: Number of partitions in the RDD.
:param seed: Seed for the RNG that generates the seed for the generator in each partition.
:return: RDD of Vector with vectors containing i.i.d samples ~ `U(0.0, 1.0)`.
>>> import numpy as np
>>> mat = np.matrix(RandomRDDs.uniformVectorRDD(sc, 10, 10).collect())
>>> mat.shape
(10, 10)
>>> mat.max() <= 1.0 and mat.min() >= 0.0
True
>>> RandomRDDs.uniformVectorRDD(sc, 10, 10, 4).getNumPartitions()
4 | def uniformVectorRDD(sc, numRows, numCols, numPartitions=None, seed=None):
"""
Generates an RDD comprised of vectors containing i.i.d. samples drawn
from the uniform distribution U(0.0, 1.0).
:param sc: SparkContext used to create the RDD.
:param numRows: Number of Vectors in the RDD.
:param numCols: Number of elements in each Vector.
:param numPartitions: Number of partitions in the RDD.
:param seed: Seed for the RNG that generates the seed for the generator in each partition.
:return: RDD of Vector with vectors containing i.i.d samples ~ `U(0.0, 1.0)`.
>>> import numpy as np
>>> mat = np.matrix(RandomRDDs.uniformVectorRDD(sc, 10, 10).collect())
>>> mat.shape
(10, 10)
>>> mat.max() <= 1.0 and mat.min() >= 0.0
True
>>> RandomRDDs.uniformVectorRDD(sc, 10, 10, 4).getNumPartitions()
4
"""
return callMLlibFunc("uniformVectorRDD", sc._jsc, numRows, numCols, numPartitions, seed) |
Generates an RDD comprised of vectors containing i.i.d. samples drawn
from the standard normal distribution.
:param sc: SparkContext used to create the RDD.
:param numRows: Number of Vectors in the RDD.
:param numCols: Number of elements in each Vector.
:param numPartitions: Number of partitions in the RDD (default: `sc.defaultParallelism`).
:param seed: Random seed (default: a random long integer).
:return: RDD of Vector with vectors containing i.i.d. samples ~ `N(0.0, 1.0)`.
>>> import numpy as np
>>> mat = np.matrix(RandomRDDs.normalVectorRDD(sc, 100, 100, seed=1).collect())
>>> mat.shape
(100, 100)
>>> abs(mat.mean() - 0.0) < 0.1
True
>>> abs(mat.std() - 1.0) < 0.1
True | def normalVectorRDD(sc, numRows, numCols, numPartitions=None, seed=None):
"""
Generates an RDD comprised of vectors containing i.i.d. samples drawn
from the standard normal distribution.
:param sc: SparkContext used to create the RDD.
:param numRows: Number of Vectors in the RDD.
:param numCols: Number of elements in each Vector.
:param numPartitions: Number of partitions in the RDD (default: `sc.defaultParallelism`).
:param seed: Random seed (default: a random long integer).
:return: RDD of Vector with vectors containing i.i.d. samples ~ `N(0.0, 1.0)`.
>>> import numpy as np
>>> mat = np.matrix(RandomRDDs.normalVectorRDD(sc, 100, 100, seed=1).collect())
>>> mat.shape
(100, 100)
>>> abs(mat.mean() - 0.0) < 0.1
True
>>> abs(mat.std() - 1.0) < 0.1
True
"""
return callMLlibFunc("normalVectorRDD", sc._jsc, numRows, numCols, numPartitions, seed) |
Generates an RDD comprised of vectors containing i.i.d. samples drawn
from the log normal distribution.
:param sc: SparkContext used to create the RDD.
:param mean: Mean of the log normal distribution
:param std: Standard Deviation of the log normal distribution
:param numRows: Number of Vectors in the RDD.
:param numCols: Number of elements in each Vector.
:param numPartitions: Number of partitions in the RDD (default: `sc.defaultParallelism`).
:param seed: Random seed (default: a random long integer).
:return: RDD of Vector with vectors containing i.i.d. samples ~ log `N(mean, std)`.
>>> import numpy as np
>>> from math import sqrt, exp
>>> mean = 0.0
>>> std = 1.0
>>> expMean = exp(mean + 0.5 * std * std)
>>> expStd = sqrt((exp(std * std) - 1.0) * exp(2.0 * mean + std * std))
>>> m = RandomRDDs.logNormalVectorRDD(sc, mean, std, 100, 100, seed=1).collect()
>>> mat = np.matrix(m)
>>> mat.shape
(100, 100)
>>> abs(mat.mean() - expMean) < 0.1
True
>>> abs(mat.std() - expStd) < 0.1
True | def logNormalVectorRDD(sc, mean, std, numRows, numCols, numPartitions=None, seed=None):
"""
Generates an RDD comprised of vectors containing i.i.d. samples drawn
from the log normal distribution.
:param sc: SparkContext used to create the RDD.
:param mean: Mean of the log normal distribution
:param std: Standard Deviation of the log normal distribution
:param numRows: Number of Vectors in the RDD.
:param numCols: Number of elements in each Vector.
:param numPartitions: Number of partitions in the RDD (default: `sc.defaultParallelism`).
:param seed: Random seed (default: a random long integer).
:return: RDD of Vector with vectors containing i.i.d. samples ~ log `N(mean, std)`.
>>> import numpy as np
>>> from math import sqrt, exp
>>> mean = 0.0
>>> std = 1.0
>>> expMean = exp(mean + 0.5 * std * std)
>>> expStd = sqrt((exp(std * std) - 1.0) * exp(2.0 * mean + std * std))
>>> m = RandomRDDs.logNormalVectorRDD(sc, mean, std, 100, 100, seed=1).collect()
>>> mat = np.matrix(m)
>>> mat.shape
(100, 100)
>>> abs(mat.mean() - expMean) < 0.1
True
>>> abs(mat.std() - expStd) < 0.1
True
"""
return callMLlibFunc("logNormalVectorRDD", sc._jsc, float(mean), float(std),
numRows, numCols, numPartitions, seed) |
Generates an RDD comprised of vectors containing i.i.d. samples drawn
from the Poisson distribution with the input mean.
:param sc: SparkContext used to create the RDD.
:param mean: Mean, or lambda, for the Poisson distribution.
:param numRows: Number of Vectors in the RDD.
:param numCols: Number of elements in each Vector.
:param numPartitions: Number of partitions in the RDD (default: `sc.defaultParallelism`)
:param seed: Random seed (default: a random long integer).
:return: RDD of Vector with vectors containing i.i.d. samples ~ Pois(mean).
>>> import numpy as np
>>> mean = 100.0
>>> rdd = RandomRDDs.poissonVectorRDD(sc, mean, 100, 100, seed=1)
>>> mat = np.mat(rdd.collect())
>>> mat.shape
(100, 100)
>>> abs(mat.mean() - mean) < 0.5
True
>>> from math import sqrt
>>> abs(mat.std() - sqrt(mean)) < 0.5
True | def poissonVectorRDD(sc, mean, numRows, numCols, numPartitions=None, seed=None):
"""
Generates an RDD comprised of vectors containing i.i.d. samples drawn
from the Poisson distribution with the input mean.
:param sc: SparkContext used to create the RDD.
:param mean: Mean, or lambda, for the Poisson distribution.
:param numRows: Number of Vectors in the RDD.
:param numCols: Number of elements in each Vector.
:param numPartitions: Number of partitions in the RDD (default: `sc.defaultParallelism`)
:param seed: Random seed (default: a random long integer).
:return: RDD of Vector with vectors containing i.i.d. samples ~ Pois(mean).
>>> import numpy as np
>>> mean = 100.0
>>> rdd = RandomRDDs.poissonVectorRDD(sc, mean, 100, 100, seed=1)
>>> mat = np.mat(rdd.collect())
>>> mat.shape
(100, 100)
>>> abs(mat.mean() - mean) < 0.5
True
>>> from math import sqrt
>>> abs(mat.std() - sqrt(mean)) < 0.5
True
"""
return callMLlibFunc("poissonVectorRDD", sc._jsc, float(mean), numRows, numCols,
numPartitions, seed) |
Generates an RDD comprised of vectors containing i.i.d. samples drawn
from the Gamma distribution.
:param sc: SparkContext used to create the RDD.
:param shape: Shape (> 0) of the Gamma distribution
:param scale: Scale (> 0) of the Gamma distribution
:param numRows: Number of Vectors in the RDD.
:param numCols: Number of elements in each Vector.
:param numPartitions: Number of partitions in the RDD (default: `sc.defaultParallelism`).
:param seed: Random seed (default: a random long integer).
:return: RDD of Vector with vectors containing i.i.d. samples ~ Gamma(shape, scale).
>>> import numpy as np
>>> from math import sqrt
>>> shape = 1.0
>>> scale = 2.0
>>> expMean = shape * scale
>>> expStd = sqrt(shape * scale * scale)
>>> mat = np.matrix(RandomRDDs.gammaVectorRDD(sc, shape, scale, 100, 100, seed=1).collect())
>>> mat.shape
(100, 100)
>>> abs(mat.mean() - expMean) < 0.1
True
>>> abs(mat.std() - expStd) < 0.1
True | def gammaVectorRDD(sc, shape, scale, numRows, numCols, numPartitions=None, seed=None):
"""
Generates an RDD comprised of vectors containing i.i.d. samples drawn
from the Gamma distribution.
:param sc: SparkContext used to create the RDD.
:param shape: Shape (> 0) of the Gamma distribution
:param scale: Scale (> 0) of the Gamma distribution
:param numRows: Number of Vectors in the RDD.
:param numCols: Number of elements in each Vector.
:param numPartitions: Number of partitions in the RDD (default: `sc.defaultParallelism`).
:param seed: Random seed (default: a random long integer).
:return: RDD of Vector with vectors containing i.i.d. samples ~ Gamma(shape, scale).
>>> import numpy as np
>>> from math import sqrt
>>> shape = 1.0
>>> scale = 2.0
>>> expMean = shape * scale
>>> expStd = sqrt(shape * scale * scale)
>>> mat = np.matrix(RandomRDDs.gammaVectorRDD(sc, shape, scale, 100, 100, seed=1).collect())
>>> mat.shape
(100, 100)
>>> abs(mat.mean() - expMean) < 0.1
True
>>> abs(mat.std() - expStd) < 0.1
True
"""
return callMLlibFunc("gammaVectorRDD", sc._jsc, float(shape), float(scale),
numRows, numCols, numPartitions, seed) |
Returns the active SparkSession for the current thread, returned by the builder.
>>> s = SparkSession.getActiveSession()
>>> l = [('Alice', 1)]
>>> rdd = s.sparkContext.parallelize(l)
>>> df = s.createDataFrame(rdd, ['name', 'age'])
>>> df.select("age").collect()
[Row(age=1)] | def getActiveSession(cls):
"""
Returns the active SparkSession for the current thread, returned by the builder.
>>> s = SparkSession.getActiveSession()
>>> l = [('Alice', 1)]
>>> rdd = s.sparkContext.parallelize(l)
>>> df = s.createDataFrame(rdd, ['name', 'age'])
>>> df.select("age").collect()
[Row(age=1)]
"""
from pyspark import SparkContext
sc = SparkContext._active_spark_context
if sc is None:
return None
else:
if sc._jvm.SparkSession.getActiveSession().isDefined():
SparkSession(sc, sc._jvm.SparkSession.getActiveSession().get())
return SparkSession._activeSession
else:
return None |
Runtime configuration interface for Spark.
This is the interface through which the user can get and set all Spark and Hadoop
configurations that are relevant to Spark SQL. When getting the value of a config,
this defaults to the value set in the underlying :class:`SparkContext`, if any. | def conf(self):
"""Runtime configuration interface for Spark.
This is the interface through which the user can get and set all Spark and Hadoop
configurations that are relevant to Spark SQL. When getting the value of a config,
this defaults to the value set in the underlying :class:`SparkContext`, if any.
"""
if not hasattr(self, "_conf"):
self._conf = RuntimeConfig(self._jsparkSession.conf())
return self._conf |
Interface through which the user may create, drop, alter or query underlying
databases, tables, functions etc.
:return: :class:`Catalog` | def catalog(self):
"""Interface through which the user may create, drop, alter or query underlying
databases, tables, functions etc.
:return: :class:`Catalog`
"""
from pyspark.sql.catalog import Catalog
if not hasattr(self, "_catalog"):
self._catalog = Catalog(self)
return self._catalog |
Create a :class:`DataFrame` with single :class:`pyspark.sql.types.LongType` column named
``id``, containing elements in a range from ``start`` to ``end`` (exclusive) with
step value ``step``.
:param start: the start value
:param end: the end value (exclusive)
:param step: the incremental step (default: 1)
:param numPartitions: the number of partitions of the DataFrame
:return: :class:`DataFrame`
>>> spark.range(1, 7, 2).collect()
[Row(id=1), Row(id=3), Row(id=5)]
If only one argument is specified, it will be used as the end value.
>>> spark.range(3).collect()
[Row(id=0), Row(id=1), Row(id=2)] | def range(self, start, end=None, step=1, numPartitions=None):
"""
Create a :class:`DataFrame` with single :class:`pyspark.sql.types.LongType` column named
``id``, containing elements in a range from ``start`` to ``end`` (exclusive) with
step value ``step``.
:param start: the start value
:param end: the end value (exclusive)
:param step: the incremental step (default: 1)
:param numPartitions: the number of partitions of the DataFrame
:return: :class:`DataFrame`
>>> spark.range(1, 7, 2).collect()
[Row(id=1), Row(id=3), Row(id=5)]
If only one argument is specified, it will be used as the end value.
>>> spark.range(3).collect()
[Row(id=0), Row(id=1), Row(id=2)]
"""
if numPartitions is None:
numPartitions = self._sc.defaultParallelism
if end is None:
jdf = self._jsparkSession.range(0, int(start), int(step), int(numPartitions))
else:
jdf = self._jsparkSession.range(int(start), int(end), int(step), int(numPartitions))
return DataFrame(jdf, self._wrapped) |
Infer schema from list of Row or tuple.
:param data: list of Row or tuple
:param names: list of column names
:return: :class:`pyspark.sql.types.StructType` | def _inferSchemaFromList(self, data, names=None):
"""
Infer schema from list of Row or tuple.
:param data: list of Row or tuple
:param names: list of column names
:return: :class:`pyspark.sql.types.StructType`
"""
if not data:
raise ValueError("can not infer schema from empty dataset")
first = data[0]
if type(first) is dict:
warnings.warn("inferring schema from dict is deprecated,"
"please use pyspark.sql.Row instead")
schema = reduce(_merge_type, (_infer_schema(row, names) for row in data))
if _has_nulltype(schema):
raise ValueError("Some of types cannot be determined after inferring")
return schema |