PYSPARK: how to visualize a GraphFrame?

问题

Suppose that I have created the following graph. My question is how can I visualize it?

 # Create a Vertex DataFrame with unique ID column "id"
    v = sqlContext.createDataFrame([
      ("a", "Alice", 34),
      ("b", "Bob", 36),
      ("c", "Charlie", 30),
    ], ["id", "name", "age"])
    # Create an Edge DataFrame with "src" and "dst" columns
    e = sqlContext.createDataFrame([
      ("a", "b", "friend"),
      ("b", "c", "follow"),
      ("c", "b", "follow"),
    ], ["src", "dst", "relationship"])
    # Create a GraphFrame
    from graphframes import *
    g = GraphFrame(v, e)

回答1:

I couldn't find any native GraphFrame library that visualizes data either.

Nevertheless, you could try to do it from DataBricks with the display() function. You can see an example here.

Also, you can try to transform the GraphFrame to python lists and use the matplotlib or the Pygraphviz libraries.

回答2:

Using Python/PySpark/Jupyter I am using the draw functionality from the networkx library. The trick is to create a networkx graph from the grapheframe graph

import networkx as nx
from graphframes import GraphFrame

def PlotGraph(edge_list):
    Gplot=nx.Graph()
    for row in edge_list.select('src','dst').take(1000):
        Gplot.add_edge(row['src'],row['dst'])

    plt.subplot(121)
    nx.draw(Gplot, with_labels=True, font_weight='bold')


spark = SparkSession \
    .builder \
    .appName("PlotAPp") \
    .getOrCreate()

sqlContext = SQLContext(spark)

vertices = sqlContext.createDataFrame([
  ("a", "Alice", 34),
  ("b", "Bob", 36),
  ("c", "Charlie", 30),
  ("d", "David", 29),
  ("e", "Esther", 32),
("e1", "Esther2", 32),
  ("f", "Fanny", 36),
  ("g", "Gabby", 60),
    ("h", "Mark", 61),
    ("i", "Gunter", 62),
    ("j", "Marit", 63)], ["id", "name", "age"])

edges = sqlContext.createDataFrame([
  ("a", "b", "friend"),
  ("b", "a", "follow"),
  ("c", "a", "follow"),
  ("c", "f", "follow"),
  ("g", "h", "follow"),
  ("h", "i", "friend"),
  ("h", "j", "friend"),
  ("j", "h", "friend"),
    ("e", "e1", "friend")
], ["src", "dst", "relationship"])

g = GraphFrame(vertices, edges)
PlotGraph(g.edges)

plot of some graph

来源：https://stackoverflow.com/questions/45720931/pyspark-how-to-visualize-a-graphframe

标签

python

apache-spark

graph

pyspark

graphframes