Wrong visualization

[jackerschott]

Take the following hepmc2 file containing a single semileptonic ttH event: events.zip and visualize this event using pyhepmc version 2.13.2 to a pdf (I am piping to dot -Tpdf > event.pdf):

with pyhepmc.open("test.hepmc") as f:
    event = f.read()
    print(to_dot(event))

The resulting event contains two W bosons (which one can easily search for in the PDF) one of which contains into a single up quark and nothing else. However if I do

import pyhepmc
import numpy as np

with pyhepmc.open("test.hepmc") as f:
    event = f.read()
    for particle in event.particles:
        if np.abs(particle.pid) == 24:
            print(len(particle.children))

I can see that len(particle.children) is 2 for both W bosons as it should be. Seems like there is a bug in the to_dot function.