import pydotplus
import matplotlib.pyplot as plt
import matplotlib.image as mpimg

style = { "bgcolor" : "#6b85d1", "fgcolor" : "#FFFFFF" }

def display_BN ( node_names, bn_struct, bn_name, style ):
    graph = pydot.Dot( bn_name, graph_type='digraph')

    # création des noeuds du réseau
    for name in node_names:
        new_node = pydot.Node( name, 
                               style="filled",
                               fillcolor=style["bgcolor"],
                               fontcolor=style["fgcolor"] )
        graph.add_node( new_node )

    # création des arcs
    for node in range ( len ( node_names ) ):
        parents = bn_struct[node]
        for par in parents:
            new_edge = pydot.Edge ( node_names[par], node_names[node] )
            graph.add_edge ( new_edge )

    # sauvegarde et affaichage
    outfile = bn_name + '.png'
    graph.write_png( outfile )
    img = mpimg.imread ( outfile )
    plt.imshow( img )