"""

Subgraph with Boundaries

========================

Draw a subgraph with bounding boxes demarcating both the nodes and the subgraphs

"""

import pygraphviz as pgv

# A graph in `.dot` format specifying two nodes, each within their own subgraph,

# and a bi-directional edge between them

dot_str = """

digraph G {

graph [compound=true];

node [shape=box];

subgraph cluster_A {

label="A";

a1 [pos="50,100!"];

}

subgraph cluster_B {

label="B";

b1 [pos="200,100!"];

}

a1 -> b1 [lhead=cluster_B, ltail=cluster_A, dir=both];

graph [bb="0,0,300,200"];

}

"""

A = pgv.AGraph(dot_str)

A.layout("dot")

A.draw("subgraph_bdries.png")