C library functions - frexp ()

C standard library - <math.h>

description

C library functionsdouble frexp (double x, int * exponent) into the floating point number x mantissa and exponent.The return value is the mantissa, and theexponent of the index is stored.The resultant value isx = mantissa * 2 ^ exponent.

statement

Here is frexp () function's declaration.

double frexp(double x, int *exponent)

parameter

• x - a floating point value to be calculated.
• exponent - a pointer to an object, the object stores the value of the exponent.

return value

This function returns the normalized decimal. If the parameter x is not zero, the decimal is normalized quadratic x, and its absolute value range from 1/2 (inclusive) to 1 (not included). If x is zero, the normalized decimal is zero and zero is stored in exp in.

Examples

The following example demonstrates frexp () function is used.

#include <stdio.h>
#include <math.h>

int main ()
{
   double x = 1024, fraction;
   int e;
   
   fraction = frexp(x, &e);
   printf("x = %.2lf = %.2lf * 2^%d\n", x, fraction, e);
   
   return(0);
}

Let's compile and run the above program, which will result in the following:

x = 1024.00 = 0.50 * 2^11

C standard library - <math.h>