Update app.py

app.py

@@ -36,7 +36,7 @@ def network_visualizer(yaxis, city, fstyear,lastyr, num_nodes):
     edges = splitIsnad(subsetEdges(city, fstyear, lastyr))[['Teacher', 'Student', yaxis]].reset_index()
     #.groupby(['Teacher', 'Student']).sum()
     if edges.shape[0] > num_nodes:
-        edge_15 = edges.sample(num_nodes)
+        edge_15 = edges.sort_values(by=yaxis, ascending=False).head(num_nodes)
     else:
         edge_15 = edges.copy()
     teacher_hadiths = edge_15[['Teacher', yaxis]].groupby('Teacher').sum().reset_index()