testBug73093.cc

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// ----------------------------------------------------------------------
//
// testBug73093 -- Test of CLHEP::Ranlux64Engine with 64 bit seeds
//
// Frank Winklmeier  2010-09-24 
// L. Garren         2010-10-21 rewritten for test suite
// 
// ----------------------------------------------------------------------
 
#include <iostream>
#include <cmath>
#include <stdlib.h>
 
#include "CLHEP/Random/Ranlux64Engine.h"
 
int valid_range( )
{
    std::ofstream output("testBug73093.cout");  
 
    int bad = 0;
    long seed;
    long mult=-235421;
    // use several seeds
    for( int il=0; il<100; ++il ) {
    if(  sizeof(long) > 4 ) {
            // using atol so 32bit compilers won't complain
            seed =       atol("9899876543210000");
        mult = mult + atol("120034020050070");
    } else {
            seed =       987654321;
        mult = mult + 12003400;
    }
    seed += il*mult;
 
    CLHEP::Ranlux64Engine rng;
    const long N = 20;
 
    rng.setSeed(seed, /*lux*/ 1);
    output <<  std::endl;
    output << "sizeof(long) = " << sizeof(long) << std::endl;
    output << "Generating " << N << " random numbers with seed " << seed << std::endl;
    output << "Using seed " << seed <<  std::endl;
 
    double sum(0);
    for (long i=0; i<N; ++i) {
      double r = rng.flat();
      if( std::abs(r) > 1.0 ) ++bad;
      output << r << std::endl;
      sum += r;
    }  
 
    output << "Sum: " << sum << std::endl;
    output << "Average: " << sum / N << std::endl;
    }
    
    return bad;
}
 
int check_sequence()
{
    // if the seed is less than 32bits long on a 64bit machine,  the random
    // number sequence should be the same as the sequence on a 32bit machine
    std::ofstream output("testBug73093.seq");  
    int bad = 0;
    long seed;
    long mult=-235421;
    // use several seeds
    for( int il=0; il<50; ++il ) {
        seed = 97654321;
    seed += il*mult;
 
    CLHEP::Ranlux64Engine rng;
    const long N = 20;
 
    rng.setSeed(seed, /*lux*/ 1);
 
        double __attribute__ ((unused)) sum = 0;
    for (long i=0; i<N; ++i) {
      double r = rng.flat();
      if( std::abs(r) > 1.0 ) ++bad;
      output << "[" << il << "][" << i << "] = " << r << ";" << std::endl;
      sum += r;
    }  
    }
    return bad;
}
 
int main()
{
 
    int bad = 0;
    bad += valid_range( );
    bad += check_sequence( );
    
    return bad;
}