tree.py 文件源码

def writePopulationDotRaw(ga_engine, filename, start=0, end=0):

        """ Writes to a raw dot file using pydot, the population of trees
        Example:
           >>> GTreeGP.writePopulationDotRaw(ga_engine, "pop.dot", 0, 10)

        This example will draw the first ten individuals of the population into
        the file called "pop.dot".

        :param ga_engine: the GA Engine
        :param filename: the filename, ie. population.dot
        :param start: the start index of individuals
        :param end: the end index of individuals
        """

        if not HAVE_PYDOT:
            utils.raiseException("You must install Pydot to use this feature !")

        pop = ga_engine.get_population()
        graph = pydot.Dot(graph_type="digraph")

        if not isinstance(pop[0], GTreeGP):
            utils.raiseException("The population must have individuals of the GTreeGP chromosome !")

        n = 0
        end_index = len(pop) if end == 0 else end
        for i in xrange(start, end_index):
            ind = pop[i]
            subg = pydot.Cluster(
                "cluster_%d" % i,
                label="\"Ind. #%d - Score Raw/Fit.: %.4f/%.4f\"" % (i, ind.getRawScore(), ind.getFitnessScore())
            )
            n = ind.writeDotGraph(subg, n)
            graph.add_subgraph(subg)

        graph.write(filename, prog='dot', format="raw")

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