Singleton pseudo-random generator

[vusak]

in the header file

#include <cstdlib>
#include <ctime>
using namespace std;
 
#define RAND_LIMIT 1000
 
class randomNormalized {
  public:
    virtual ~randomNormalized() {}
 
    static float generate(void);
 
  protected:
    randomNormalized() {}
 
  private:
    static bool randomNotSeeded;
};
 

in the source file

#include "ggUtilityFunctions.hpp"
 
float randomNormalized::generate(void) {
  if(randomNotSeeded) {
    srand(static_cast<unsigned int>(time(NULL)));
    randomNotSeeded = false;
  }
  return (float)(rand() % RAND_LIMIT) / (float)RAND_LIMIT;
}
 

for use in a file

#include <algorithm>
#include <vector>
 
void foo() {
  generate(inputWeights.begin(), inputWeights.end(), randomNormalized::generate);
}
 

im getting an unresolved external error for the "randomNormalized::randomNotSeeded" during linking

my goal is to have a simple function object to pass to generate which produces random floats in the range [0,1]. this function object will be called many many times, so i only want srand() to be called once, therefore i need the function object only be created once.

any ideas?

thanks

[JosAH]

in the header file
im getting an unresolved external error for the "randomNormalized::randomNotSeeded" during linking

any ideas?

thanks

Define that static member variable in your .cpp file too.

kind regards,

Jos

[AdrianH]

Look here under fiasco. It is a pain in the posterior, but it is an unfortunate reality. :(


Adrian