Pass seed from ProductionMechanism to BreitWignerGenerator

src/libraries/AMPTOOLS_MCGEN/BreitWignerGenerator.cc

@@ -4,6 +4,7 @@
 #include <cassert>
 
 #include "AMPTOOLS_MCGEN/BreitWignerGenerator.h"
+#include "TRandom3.h"
 
 const double BreitWignerGenerator::kPi = 3.14159;
 
@@ -12,10 +13,12 @@ m_mass( 0 ),
 m_width( 0 )
 {}
 
-BreitWignerGenerator::BreitWignerGenerator( double mass, double width ) :
+BreitWignerGenerator::BreitWignerGenerator( double mass, double width, int seed ) :
 m_mass( mass ),
 m_width( width )
-{}
+{
+    gRandom->SetSeed( seed );
+}
 
 pair< double, double >
 BreitWignerGenerator::operator()() const
@@ -61,5 +64,5 @@ BreitWignerGenerator::pdf( double s ) const {
 double
 BreitWignerGenerator::random( double low, double hi ) const {
 
-	return( ( hi - low ) * drand48() + low );
+	return( ( hi - low ) * gRandom->Uniform() + low );
 }

src/libraries/AMPTOOLS_MCGEN/BreitWignerGenerator.h

@@ -12,7 +12,7 @@ class BreitWignerGenerator
 
         BreitWignerGenerator();
 
-        BreitWignerGenerator( double mass, double width );
+        BreitWignerGenerator( double mass, double width, int seed = 0 );
 
         // output of the generation is a pair of doubles
         // the first is the mass and the second is the weight

src/libraries/AMPTOOLS_MCGEN/ProductionMechanism.cc

@@ -20,7 +20,8 @@ m_highMass( 0 ),
 m_slope( slope ),
 m_lowT( 0 ),
 m_highT( 12 ),
-m_lastWeight( 1. )
+m_lastWeight( 1. ),
+m_seed( seed )
 {	
   // kMZ = 108.;      //  mass of Sn116 
   kMZ = 208.*0.931494;      //  use mass of Pb as it is in the particle table
@@ -210,7 +211,7 @@ void
 ProductionMechanism::addResonance( double mass, double width, double crossSec ){
 
   m_decGen.addChannel( m_bwGen.size(), crossSec );
-  m_bwGen.push_back( BreitWignerGenerator( mass, width ) );
+  m_bwGen.push_back( BreitWignerGenerator( mass, width, m_seed ) );
 }
 
 double

src/libraries/AMPTOOLS_MCGEN/ProductionMechanism.h

@@ -53,6 +53,8 @@ class ProductionMechanism
 	double m_highT;
 
 	double m_recMass;
+
+	int m_seed;
 
 	bool isBaryonResonance;