cpolar

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

Usage

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

cpolar( z )

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

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

var o = cpolar( new Complex128( 5.0, 3.0 ) );
// returns [ ~5.83, ~0.5404 ]

cpolar.assign( z, out, stride, offset )

Computes the absolute value and phase of a double-precision complex floating-point number and assigns results to a provided output array.

var Complex128 = require( '@stdlib/complex/float64/ctor' );
var Float64Array = require( '@stdlib/array/float64' );

var out = new Float64Array( 2 );

var v = cpolar.assign( new Complex128( 5.0, 3.0 ), out, 1, 0 );
// returns <Float64Array>[ ~5.83, ~0.5404 ]

var bool = ( v === out );
// returns true

Examples

var Complex128 = require( '@stdlib/complex/float64/ctor' );
var randu = require( '@stdlib/random/base/randu' );
var round = require( '@stdlib/math/base/special/round' );
var real = require( '@stdlib/complex/float64/real' );
var imag = require( '@stdlib/complex/float64/imag' );
var cpolar = require( '@stdlib/math/base/special/cpolar' );

var re;
var im;
var z;
var o;
var i;

for ( i = 0; i < 100; i++ ) {
    re = round( randu()*100.0 ) - 50.0;
    im = round( randu()*100.0 ) - 50.0;
    z = new Complex128( re, im );
    o = cpolar( z );
    z = z.toString();
    console.log( 'abs(%s) = %d. arg(%s) = %d', z, o[0], z, o[1] );
}

C APIs

Usage

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

stdlib_base_cpolar( z, cabs, cphase )

Computes the absolute value and phase of 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( 5.0, 3.0 );
double cabs;
double cphase;
stdlib_base_cpolar( z, &cabs, &cphase );

The function accepts the following arguments:

z: [in] stdlib_complex128_t input value.
cabs: [out] double* destination for the absolute value.
cphase: [out] double* destination for the phase value in radians.

double stdlib_base_cpolar( const stdlib_complex128_t z, double *cabs, double *cphase );

Examples

#include "stdlib/math/base/special/cpolar.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 )
    };

    double cphase;
    double cabs;
    double re;
    double im;
    int i;
    for ( i = 0; i < 4; i++ ) {
        stdlib_base_cpolar( x[i], &cabs, &cphase );
        stdlib_complex128_reim( x[i], &re, &im );
        printf( "cpolar(%lf + %lfi) => cabs: %lf, cphase: %lf\n", re, im, cabs, cphase );
    }
}