Syntax

#include <math.h>
double ldexp(double x, int exp);

ldexp calculates the value of x * (2exp).

ldexp returns the value of x*(2exp). If an overflow results, the function returns +HUGE_VAL for a large result or -HUGE_VAL for a small result, and sets errno to ERANGE.

This example computes y as 1.5 times 2 to the fifth power (1.5*25):

#include <math.h>

int main(void)
{
   double x,y;
   int p;

   x = 1.5;
   p = 5;
   y = ldexp(x, p);
   printf("%lf times 2 to the power of %d is %lf\n", x, p, y);
   return 0;

   /****************************************************************************
      The output should be:

      1.500000 times 2 to the power of 5 is 48.000000
   ****************************************************************************/
}

• exp
  
• frexp
  
• modf

---

[Back] [Next]