@stdlib/math-base-special-csignum v0.2.1
csignum
Evaluate the signum function of a double-precision complex floating-point number.
Installation
npm install @stdlib/math-base-special-csignum
Usage
var csignum = require( '@stdlib/math-base-special-csignum' );
csignum( z )
Evaluates the signum function of 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 v = csignum( new Complex128( -4.2, 5.5 ) );
// returns <Complex128>
var re = real( v );
// returns -0.6069136033622302
var im = imag( v );
// returns 0.79476781392673
v = csignum( new Complex128( 0.0, 0.0 ) );
// returns <Complex128>
re = real( v );
// returns 0.0
im = imag( v );
// returns 0.0
v = csignum( new Complex128( NaN, NaN ) );
// returns <Complex128>
re = real( v );
// returns NaN
im = imag( v );
// returns NaN
Examples
var uniform = require( '@stdlib/random-base-uniform' ).factory;
var Complex128 = require( '@stdlib/complex-float64' );
var csignum = require( '@stdlib/math-base-special-csignum' );
var rand = uniform( -50.0, 50.0 );
var z;
var i;
for ( i = 0; i < 100; i++ ) {
z = new Complex128( rand(), rand() );
console.log( 'csignum(%s) = %s', z, csignum( z ) );
}
C APIs
Usage
#include "stdlib/math/base/special/csignum.h"
stdlib_base_csignum( z )
Evaluates the signum function of 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( -4.2, 5.5 );
stdlib_complex128_t out = stdlib_base_csignum( z );
double re = stdlib_real( out );
// returns -0.6069136033622302
double im = stdlib_imag( out );
// returns 0.79476781392673
The function accepts the following arguments:
- z:
[in] stdlib_complex128_t
input value.
stdlib_complex128_t stdlib_base_csignum( const stdlib_complex128_t z );
Examples
#include "stdlib/math/base/special/csignum.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 re1;
double im1;
double re2;
double im2;
int i;
for ( i = 0; i < 4; i++ ) {
v = x[ i ];
y = stdlib_base_csignum( v );
stdlib_reim( v, &re1, &im1 );
stdlib_reim( y, &re2, &im2 );
printf( "csignum(%lf + %lfi) = %lf + %lfi\n", re1, im1, re2, im2 );
}
}
See Also
@stdlib/math-base/special/signum
: evaluate the signum function for 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.