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cneg
Negate a double-precision complex floating-point number.
Installation
npm install @stdlib/math-base-ops-cnegUsage
var cneg = require( '@stdlib/math-base-ops-cneg' );cneg( z )
Negates a double-precision complex floating-point number.
var Complex128 = require( '@stdlib/complex-float64' );
var real = require( '@stdlib/complex-real' );
var imag = require( '@stdlib/complex-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 NaNExamples
var Complex128 = require( '@stdlib/complex-float64' );
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.h"
#include "stdlib/complex/real.h"
#include "stdlib/complex/imag.h"
stdlib_complex128_t z = stdlib_complex128( 3.0, -2.0 );
stdlib_complex128_t out = stdlib_base_cneg( z );
double re = stdlib_real( out );
// returns -3.0
double im = stdlib_imag( out );
// returns 2.0The function accepts the following arguments:
-
z:
[in] stdlib_complex128_tinput value.
stdlib_complex128_t stdlib_base_cneg( const stdlib_complex128_t z );Examples
#include "stdlib/math/base/ops/cneg.h"
#include "stdlib/complex/float64.h"
#include "stdlib/complex/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_reim( v, &re, &im );
printf( "z = %lf + %lfi\n", re, im );
y = stdlib_base_cneg( v );
stdlib_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.