cabs

Compute the absolute value of a double-precision complex floating-point number.

The absolute value of a complex number is defined as

which corresponds to the length of a vector from the origin to a complex value plotted in the complex plane.

Installation

npm install @stdlib/math-base-special-cabs

Usage

var cabs = require( '@stdlib/math-base-special-cabs' );

cabs( z )

Computes an absolute value of a double-precision complex floating-point number.

var Complex128 = require( '@stdlib/complex-float64-ctor' );

var y = cabs( new Complex128( 5.0, 3.0 ) );
// returns ~5.83

Examples

var Complex128 = require( '@stdlib/complex-float64-ctor' );
var discreteUniform = require( '@stdlib/random-base-discrete-uniform' );
var cabs = require( '@stdlib/math-base-special-cabs' );

var z;
var i;
for ( i = 0; i < 100; i++ ) {
    z = new Complex128( discreteUniform( -50, 50 ), discreteUniform( -50, 50 ) );
    console.log( 'cabs(%s) = %d', z.toString(), cabs( z ) );
}

C APIs

Usage

#include "stdlib/math/base/special/cabs.h"

stdlib_base_cabs( z )

Computes the absolute value of a double-precision complex floating-point number.

#include "stdlib/complex/float64/ctor.h"

stdlib_complex128_t z = stdlib_complex128( 5.0, 3.0 );

double y = stdlib_base_cabs( z );
// returns ~5.83

The function accepts the following arguments:

• z: [in] stdlib_complex128_t input value.

double stdlib_base_cabs( const stdlib_complex128_t complex z );

Examples

#include "stdlib/math/base/special/cabs.h"
#include "stdlib/complex/float64/ctor.h"
#include "stdlib/complex/float64/reim.h"
#include <stdio.h>

int main( void ) {
    const stdlib_complex128_t x[] = {
        stdlib_complex128( 3.14, 1.0 ),
        stdlib_complex128( -3.14, -1.0 ),
        stdlib_complex128( 0.0, 0.0 ),
        stdlib_complex128( 0.0/0.0, 0.0/0.0 )
    };

    stdlib_complex128_t v;
    double re;
    double im;
    double y;
    int i;
    for ( i = 0; i < 4; i++ ) {
        v = x[ i ];
        y = stdlib_base_cabs( v );
        stdlib_complex128_reim( v, &re, &im );
        printf( "f(%lf + %lf) = %lf\n", re, im, y );
    }
}

See Also

• @stdlib/math-base/special/cabs2: compute the squared absolute value of a double-precision complex floating-point number.
• @stdlib/math-base/special/abs: compute the absolute value of a double-precision floating-point number.

Notice

This package is part of stdlib, a standard library for JavaScript and Node.js, with an emphasis on numerical and scientific computing. The library provides a collection of robust, high performance libraries for mathematics, statistics, streams, utilities, and more.

For more information on the project, filing bug reports and feature requests, and guidance on how to develop stdlib, see the main project repository.

Community

License

See LICENSE.

Copyright

Copyright © 2016-2024. The Stdlib Authors.