GSI Forum
GSI Helmholtzzentrum für Schwerionenforschung

Home » PANDA » PandaRoot » General » TGeoMixture SetIndex function
TGeoMixture SetIndex function Mon, 02 May 2011 15:37
 Maria Patsyuk Messages: 58Registered: April 2010 continuous participant From: *gsi.de
Hello,

there is a function called "SetIndex()" in TGeoMixture class.
What does this index mean?

For example if I define a number of media for the detector geometry (an example for Fused Sil medium follows), what should these indices for each of my medium mean?
Should they be unique? Where are they later used?

// Mixture: FusedSil
nel = 2;
density = 2.200000;
TGeoMixture* FusedSil = new TGeoMixture("FusedSil", nel,density);
aa = 28.090000; z = 14.000000; w = 0.467475; // SI
FusedSil->DefineElement(0,aa,z,w);
aa = 15.999400; z = 8.000000; w = 0.532525; // O
FusedSil->DefineElement(1,aa,z,w);
FusedSil->SetIndex(0);
// Medium: FusedSil
numed = 1; // medium number
par[0] = 1.000000; // isvol
par[1] = 1.000000; // ifield
par[2] = 20.000000; // fieldm
par[3] = -1.000000; // tmaxfd
par[4] = -1.000000; // stemax
par[5] = -1.000000; // deemax
par[6] = 0.001000; // epsil
par[7] = -1.000000; // stmin
TGeoMedium *FusedSil_m = new TGeoMedium("FusedSil", numed,FusedSil, par);

Thank you
Re: TGeoMixture SetIndex function [message #11740 is a reply to message #11729] Wed, 04 May 2011 15:36
 Mohammad Al-Turany Messages: 518Registered: April 2004 Location: GSI, Germany first-grade participant From: *gsi.de
Hi,

You do not need to set this index, at the end of geometry constructiona SetIndexAll() method will be called (internally, you do not need to call it), this method take care that each material or mixture has a unique index.

regards