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Warning "G4RandExponential" doesn't seem to work -- known, or a bug? 

Forum: Documentation and Examples
Date: 26 Apr, 2011
From: Michael H. Kelsey <Michael H. Kelsey>

I want to generate random timestamps for events based on the "known" strength of my radioactive source and the area of the source visible through my collimator.

I wrote what should be a trivial code fragment to do this:

  #include "Randomize.hh"
[...]
  G4double decayTau = (ActiveVisible[iCan]/ActiveSurface[iCan]
		       / SourceActivity[iCan]);
  G4double decayInterval = G4RandExponential::shoot(decayTau);
[...]

where "iCan" is just the index of which of my source canisters I'm using for this event, ActiveVisible and ActiveSurface are both areas, and SourceActivity is in becquerels, so decayTau comes out as an effective lifetime in seconds).

The code does not compile:

  Compiling Am241SourceHolder.cc ...
  Am241SourceHolder.cc: In member function 'G4double Am241SourceHolder::GenerateDecayTime(G4int)':
  Am241SourceHolder.cc:180: error: 'G4RandExponential' has not been declared
  Am241SourceHolder.cc:180: error: 'shoot' was not declared in this scope
  make[4]: *** [/Users/kelsey/cdms/cdmsim/tmp/Darwin-g++/CDMSgeometry/Am241SourceHolder.o] Error 1

If I look in Randomize.hh, I see the use of a #define, rather than a typedef:

[...]
  #define G4RandGauss CLHEP::RandGaussQ
  #define G4RandExponential CLHEP::RandExponential
[...]

This looks wrong to me. I cannot find ANY bit of code, either in "examples" or in "source" where G4RandExponential is actually used. Are these #define's left over from some early development work that never went through?

  -- Michael Kelsey

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1 Question: Re: G4RandExponential" doesn't seem to work -- known, or a bug?   (Gabriele Cosmo - 28 Apr, 2011)
(_ None: Re: G4RandExponential" doesn't seem to work -- known, or a bug?   (Mike Kelsey - 28 Apr, 2011)
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