modf()

break a number into integral and fractional parts

Synopsis:

#include <math.h>
double modf( double value, double *iptr );

Description:

The modf() function breaks the argument value into integral and fractional parts, each of which has the same sign as the argument. It stores the integral part as a double in the object pointed to by iptr.

Returns:

The signed fractional part of value.

Examples:

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

void main()
  {
    double integral_value, fractional_part;

    fractional_part = modf( 4.5, &integral_value );
    printf( "%f %f\n", fractional_part, integral_value );
    fractional_part = modf( -4.5, &integral_value );
    printf( "%f %f\n", fractional_part, integral_value );
  }

produces the output:

0.500000 4.000000
-0.500000 -4.000000

Classification:

ANSI

See also:

frexp(), ldexp()