pretty printing graphs

[Michele Simionato]

"Scherer, Bill" <Bill.Scherer at verizonwireless.com> wrote in message news:<mailman.1059413382.3564.python-list at python.org>...

Hey "dot" is great! I didn't know about it before readin your post.

In a very short time I came out with the following recipe to draw
Python inheritance hierarchies (which I post since it is pretty
short and useful ;):


"How to draw inheritance hierarchies via dot"

import os

def label(i,n):
    if n>1: return '[label="%s"]' % (i+1)
    return ""

def dotMRO(cls):
    "Generates the dot code for the MRO directed graph"
    yield "digraph MRO_of_%s{\n" % cls.__name__
    for c in cls.__mro__:
        n=len(c.__bases__)
        yield ' '.join(['  %s -> %s %s;' % (b.__name__,c.__name__,label(i,n))
                         for i,b in enumerate(c.__bases__)])
    yield '}'

# Example hierarchy    
O = object
class F(O): pass
class E(O): pass
class D(O): pass
class G(O): pass
class C(F,D,G): pass
class B(E,D): pass
class A(B,C): pass

# creates the graph
dotcode='\n'.join(dotMRO(A)); print dotcode
os.system('echo "%s" | dot -Tps > prova.ps' % dotcode)
os.system('gv prova.ps&')

Assuming you have "dot" and the standard Unix tools installed this 
will generate a very nice diagram. I am open to suggestion to improve it,  
since this is may first trial with "dot". I am quite impressed by the
easy of use.

Very nice!


            Michele