C++ Program to Generate Random Numbers Using Probability Distribution Function

Probability Density Function (pdf), is a function that describes the relative likelihood for this random variable to take on a given value. It is also called as density of a continuous random variable.

The probability of the random variable fall within a particular range of values is given by the integral of this variable’s density over that range, So, it is given by the area under the density function but above the horizontal axis and between the lowest and greatest values of the range. Probability Distribution is based upon this probability density function.

Algorithm

Begin
   Declare n
   Assign pdf=0
   For i =0 to n , do
      pdf = rand() mod 200
      If pdf greater than 360
         Print 1
      Else if pdf less than 0
         Print 0
      Else
         Print pdf * 0.1 / 360
      Done
   Done
end

Example Code

#include <iostream>
using namespace std;
int n = 6;
int main(int argc, char **argv) {
   int pdf = 0;
   for (int i = 0; i < n; i++) {
      pdf = rand() % 200;
      if (pdf > 360)
         cout << 1 << " ";
      else if (pdf < 0)
         cout << 0 << " ";
      else
         cout << pdf * 0.1 / 360 << " ";
   }
   cout << "...";
}

Output

0.0508333 0.0238889 0.0491667 0.0319444 0.0536111 0.0375 ...