Using scripting in a PChannel

{ 

    PFireball *source = new PFireball("w", 1.0, 0.055, 0.0, 1.0, 0.0, 0., 0., 0., 0.); //1AGeV temp.
    source->setTrueThermal(kFALSE);

    PParticle *w = new PParticle("w");
    PParticle *s1[] = {source, w};
    PChannel  *c1 = new PChannel(s1, 1, 1);

    c1->Do("loop: [w]->SetM({w_bw}->SampleTotalMass()); if ([w]->M() > 0.85) goto loop");

    PParticle *ep = new PParticle("mu+");
    PParticle *em = new PParticle("mu-");
    PParticle *pi = new PParticle("pi0");
    PParticle *dm = new PParticle("dimuon");
    PParticle *s2[] = {w, dm, pi};
    PChannel  *c2 = new PChannel(s2, 2, 1);

    PChannel  *cc[] = {c1, c2};
    PReaction *r = new PReaction(cc, "thermal_w", 2);
    TH1F *histo  = new TH1F("histo", "mumu mass", 100, 0.1, 1.2);
    TH1F *histo2 = new TH1F("histo2", "w mass", 100, 0.1, 1.2);
    r->Do(histo, "_x = ([dimuon])->M()");
    r->Do(histo2, "_x = ([w])->M()");
    r->Print();
    r->loop(10000);

    histo2->Draw();

    //data->Draw("M()","ID()==41","");

}