cneg

Negate a double-precision complex floating-point number.

Installation

npm install @stdlib/math-base-ops-cneg

Usage

var cneg = require( '@stdlib/math-base-ops-cneg' );

cneg( z )

Negates a double-precision complex floating-point number.

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

var z = new Complex128( -4.2, 5.5 );

var out = cneg( z );
// returns <Complex128>

var re = real( out );
// returns 4.2

var im = imag( out );
// returns -5.5

z = new Complex128( 0.0, 0.0 );

out = cneg( z );
// returns <Complex128>

re = real( out );
// returns -0.0

im = imag( out );
// returns -0.0

z = new Complex128( NaN, NaN );

out = cneg( z );
// returns <Complex128>

re = real( out );
// returns NaN

im = imag( out );
// returns NaN

Examples

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

function randomComplex() {
    var re = discreteUniform( -50, 50 );
    var im = discreteUniform( -50, 50 );
    return new Complex128( re, im );
}

var z;
var o;
var i;

for ( i = 0; i < 100; i++ ) {
    z = randomComplex();
    o = cneg( z );
    console.log( 'negate(%s) = %s', z.toString(), o.toString() );
}

C APIs

Usage

#include "stdlib/math/base/ops/cneg.h"

stdlib_base_cneg( z )

Negates a double-precision complex floating-point number.

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

stdlib_complex128_t z = stdlib_complex128( 3.0, -2.0 );

stdlib_complex128_t out = stdlib_base_cneg( z );

double re = stdlib_complex128_real( out );
// returns -3.0

double im = stdlib_complex128_imag( out );
// returns 2.0

The function accepts the following arguments:

• z: [in] stdlib_complex128_t input value.

stdlib_complex128_t stdlib_base_cneg( const stdlib_complex128_t z );

Examples

#include "stdlib/math/base/ops/cneg.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, 1.5 ),
        stdlib_complex128( -3.14, 1.5 ),
        stdlib_complex128( 0.0, -0.0 ),
        stdlib_complex128( 0.0/0.0, 0.0/0.0 )
    };

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

        y = stdlib_base_cneg( v );
        stdlib_complex128_reim( y, &re, &im );
        printf( "cneg(z) = %lf + %lfi\n", re, im );
    }
}

See Also

• @stdlib/math-base/special/cabs: compute the absolute value of a double-precision complex 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.