def visualise_graph(Gx, filename):
try:
import pygraphviz as pgv
except ImportError:
raise RuntimeError("Install pygraphviz")
if Gx.number_of_nodes() > 400:
print("Skipping visualisation")
return
G = pgv.AGraph(strict=False, directed=True)
for nd, v in Gx.nodes.items():
ex = v['expression']
label = ex.__class__.__name__
if isinstance(ex, Sum):
label = '+'
elif isinstance(ex, Product):
label = '*'
elif isinstance(ex, Division):
label = '/'
elif isinstance(ex, (IntValue, FloatValue)):
label = ex.value()
elif isinstance(ex, (Indexed, ReferenceValue)):
label = str(ex)
G.add_node(nd, label='[%d] %s' % (nd, label))
arg = strip_modified_terminal(ex)
if isinstance(arg, Argument):
G.get_node(nd).attr['shape'] = 'box'
t = v.get('target')
if t:
G.get_node(nd).attr['label'] += ':' + str(t)
G.get_node(nd).attr['shape'] = 'hexagon'
c = v.get('component')
if c:
G.get_node(nd).attr['label'] += ', comp={}'.format(c)
for nd, eds in Gx.out_edges.items():
for ed in eds:
G.add_edge(nd, ed)
G.layout(prog='dot')
G.draw(filename)
def build_argument_indices(S):
"""Build ordered list of indices to modified arguments."""
arg_indices = []
for i, v in S.nodes.items():
arg = strip_modified_terminal(v['expression'])
if isinstance(arg, Argument):
arg_indices.append(i)
# Make a canonical ordering of vertex indices for modified arguments
def arg_ordering_key(i):
"""Return a key for sorting argument vertex indices.
Key is based on the properties of the modified terminal."""
mt = analyse_modified_terminal(S.nodes[i]['expression'])
return mt.argument_ordering_key()
ordered_arg_indices = sorted(arg_indices, key=arg_ordering_key)
return ordered_arg_indices