Problem 1699 - The Ranecu engine produces the same results irrespective of seeds
Summary: The Ranecu engine produces the same results irrespective of seeds
Status: RESOLVED INVALID
Alias: None
Product: Geant4
Classification: Unclassified
Component: run (show other problems)
Version: 10.0
Hardware: Apple Linux
: P5 trivial
Assignee: Gabriele Cosmo
URL:
Depends on:
Blocks:
 
Reported: 2014-12-12 17:03 CET by Padraig
Modified: 2015-01-20 09:09 CET (History)
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Description Padraig 2014-12-12 17:03:17 CET 
If I call 

    G4Random::setTheEngine(new CLHEP::RanecuEngine());
    G4Random::setTheSeed(systime);

in my main method I get the same results even if the seeds are different. 

Using the standard engine I have the expected behaviour.
Comment 1 Gabriele Cosmo 2015-01-20 09:09:09 CET 
RanecuEngine for SetTheSeed() uses a predefined table for setting the seed, i.e. the result of calling SetTheSeed(seed) is an index used to access the table computed module the size of the table... as result you may have the same index and therefore the same initial seeds.
You should a couple of seeds with SetTheSeeds() to properly initialise RanecuEngine.