Create indicators/bollinger_bands.py

indicators/bollinger_bands.py

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+import pandas as pd
+
+def calculate_bollinger_bands(data, column='close', period=21, std_multiplier=1.7):
+    """
+    Calculates Bollinger Bands for a specified column in the data DataFrame.
+
+    Args:
+        data (pd.DataFrame): The input DataFrame containing the price data.
+        column (str): The name of the column to calculate the Bollinger Bands on. Default is 'close'.
+        period (int): The period over which to calculate the SMA and standard deviation. Default is 21.
+        std_multiplier (float): The multiplier for the standard deviation to define the width of the bands. Default is 1.7.
+
+    Returns:
+        pd.DataFrame: The input DataFrame augmented with Bollinger Bands ('BB_Middle', 'BB_Upper', 'BB_Lower').
+    """
+    # Calculate the SMA for the specified period
+    data['BB_Middle'] = data[column].rolling(window=period).mean()
+    
+    # Calculate the standard deviation
+    std_dev = data[column].rolling(window=period).std()
+    
+    # Calculate the upper and lower Bollinger Bands
+    data['BB_Upper'] = data['BB_Middle'] + (std_multiplier * std_dev)
+    data['BB_Lower'] = data['BB_Middle'] - (std_multiplier * std_dev)
+    
+    return data
+
+# Example usage:
+# Assuming `data` is a pandas DataFrame with a 'close' column:
+# data_with_bbands = calculate_bollinger_bands(data, column='close', period=21, std_multiplier=1.7)