fdim

Return zero if x is smaller than or equal to y, or return a value of x - y if x is greater than y.

Interface Definition

C interface:

float fdimf(float x, float y);

double fdim(double x, double y);

Parameters

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

Return Value

errno: If the return value is inf, it is set to ERANGE.
If x < y, the return value is 0.
If x ≥ y, the return value is x – y.
If x or y is NaN, the return value is NaN.

Dependencies

C: "km.h"

Examples

C interface:

    // typical usage
    printf("fdim(1.0, 2.0) = %.15f\n", fdim(1.0, 2.0));
    printf("fdim(3.0, 2.0) = %.15f\n", fdim(3.0, 2.0));
    // special handling
    printf("fdim(INFINITY, INFINITY) = %.15f\n", fdim(INFINITY, INFINITY));
    printf("fdim(INFINITY, -INFINITY) = %.15f\n", fdim(INFINITY, -INFINITY));
    printf("fdim(-INFINITY, INFINITY) = %.15f\n", fdim(-INFINITY, INFINITY));
    printf("fdim(-INFINITY, -INFINITY) = %.15f\n", fdim(-INFINITY, -INFINITY));
    printf("fdim(NAN, -INFINITY) = %.15f\n", fdim(NAN, -INFINITY));

 result
   /* 
    * fdim(1.0, 2.0) = 0.000000000000000
    * fdim(3.0, 2.0) = 1.000000000000000
    * fdim(INFINITY, INFINITY) = 0.000000000000000
    * fdim(INFINITY, -INFINITY) = inf
    * fdim(-INFINITY, INFINITY) = 0.000000000000000
    * fdim(-INFINITY, -INFINITY) = 0.000000000000000
    * fdim(NAN, -INFINITY) = nan
    * */

Parent topic: Miscellaneous Functions