fabs

Return the absolute value of the input floating point number.

Interface Definition

C interface:

float fabsf(float x);

double fabs(double x);

Parameters

Parameter	Type	Description	Input/Output
x	For fabsf, x is of single-precision floating-point type. For fabs, x is of double-precision floating-point type.	Floating-point value of the input data.	Input

Return Value

If input x is ±0, the return value is +0.
If input x is ±∞, the return value is +∞.
If input x is ±NaN, the return value is NaN.

Dependency

C: "km.h"

Example

C interface:

    // typical usage
    printf("fabs(1.0) = %.15f\n", fabs(1.0));
    printf("fabs(-3.0) = %.15f\n", fabs(-3.0));
    // special handing
    printf("fabs(NAN) = %.15f\n", fabs(NAN));
    printf("fabs(-NAN) = %.15f\n", fabs(-NAN));
    printf("fabs(INFINITY) = %.15f\n", fabs(INFINITY));
    printf("fabs(-INFINITY) = %.15f\n", fabs(-INFINITY));

 result
   /* 
     * fabs(1.0) = 1.000000000000000 
     * fabs(-3.0) = 3.000000000000000
     * fabs(NAN) = nan
     * fabs(-NAN) = nan
     * fabs(INFINITY) = inf
     * fabs(-INFINITY) = inf
     * */

Parent topic: Miscellaneous Functions