cabs

Return the absolute value of a complex number.

Interface Definition

C interface:

float cabsf(float complex x);

double cabs(double complex x);

double cabs_18(double complex x);

long double cabsl(long double complex x);

cabs_18 is provided only in the high-precision version.

Parameters

Parameter	Type	Description	Input/Output
x	For cabsf, x is of complex single-precision floating-point type. For cabs and cabs_18, x is of complex double-precision floating-point type. For cabsl, x is of complex, long, double-precision floating-point type.	Floating-point value of the input data.	Input

Return Value

The absolute value of x is returned.
If x.real or x.imag is SNaN, NaN is returned.
If x.real or x.imag is ±∞, ±∞ is returned.
If x.real or x.imag is QNaN, NaN is returned.
If x.real is ±0 and x.imag is ±0, +0 is returned.
If , +∞ is returned.

Dependency

C: "km.h"

Example

C interface:

    // typical usage
    double x1 = INFINITY, y1 = INFINITY;
    double x2 = 2.0, y2 = 3.0;
    double x3 = -2.5, y3 = -3.4;
    double x4 = NAN, y4 = NAN;
    double x5 = 0, y5 = 0;
    // print result
    printf("cabs(%.2f + %.2f*I) = %.6f\n", x1, y1, cabs(__builtin_complex(x1, y1)));
    printf("cabs(%.2f + %.2f*I) = %.6f\n", x2, y2, cabs(__builtin_complex(x2, y2)));
    printf("cabs(%.2f + %.2f*I) = %.6f\n", x3, y3, cabs(__builtin_complex(x3, y3)));
    printf("cabs(%.2f + %.2f*I) = %.6f\n", x4, y4, cabs(__builtin_complex(x4, y4)));
    printf("cabs(%.2f + %.2f*I) = %.6f\n", x5, y5, cabs(__builtin_complex(x5, y5)));

   /*
    * cabs(inf + inf*I) = inf
    * cabs(2.00 + 3.00*I) = 3.605551
    * cabs(-2.50 + -3.40*I) = 4.220190
    * cabs(nan + nan*I) = nan
    * cabs(0.00 + 0.00*I) = 0.000000
    **/

Parent topic: Complex Functions