title: Color a particular node in Networkx and Graphviz
body: <p>I am writing a program to plot a graph from a distance matrix. It is working fine.
  Now I want a certain node and a certain edge to be of a particular color of my choice. How do I do that?</p>
  
  <p>The program is in Python and uses Networkx and Graphviz</p>
  
  <pre><code>import networkx as nx
  import numpy as np
  import pickle
  from random import randint
  
  p_file = open('pickles/distance')
  Dist = pickle.load(p_file)
  p_file.close()
  p_file = open('pickles/names')
  Names = pickle.load(p_file)
  p_file.close()
  
  dt = [('len', float)]
  A = np.array(Dist)*5
  A = A.view(dt)
  
  G = nx.from_numpy_matrix(A)
  G = nx.relabel_nodes(G, dict(zip(range(len(G.nodes())),Names)))    
  
  G = nx.to_agraph(G)
  G.node_attr.update(ndcolor="red", node="DC", style="filled")
  G.edge_attr.update(color="none")
  G.draw('P1.png', format='png', prog='neato')
  </code></pre>