Skip to content

div

Directory actions

More options

Directory actions

More options

Latest commit

 

History

History

div

README.md

cdiv

Divide two double-precision complex floating-point numbers.

Usage

var cdiv = require( '@stdlib/complex/float64/base/div' );

cdiv( z1, z2 )

Divides two double-precision complex floating-point numbers.

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

var z1 = new Complex128( -13.0, -1.0 );
var z2 = new Complex128( -2.0, 1.0 );

var v = cdiv( z1, z2 );
// returns <Complex128>[ 5.0, 3.0 ]

cdiv.assign( re1, im1, re2, im2, out, strideOut, offsetOut )

Divides two double-precision complex floating-point numbers and assigns results to a provided output array.

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

var out = new Float64Array( 2 );
var v = cdiv.assign( -13.0, -1.0, -2.0, 1.0, out, 1, 0 );
// returns <Float64Array>[ 5.0, 3.0 ]

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

The function supports the following parameters:

  • re1: real component of the first complex number.
  • im1: imaginary component of the first complex number.
  • re2: real component of the second complex number.
  • im2: imaginary component of the second complex number.
  • out: output array.
  • strideOut: stride length for out.
  • offsetOut: starting index for out.

cdiv.strided( z1, sz1, oz1, z2, sz2, oz2, out, so, oo )

Divides two double-precision complex floating-point numbers stored in real-valued strided array views and assigns results to a provided strided output array.

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

var z1 = new Float64Array( [ -13.0, -1.0 ] );
var z2 = new Float64Array( [ -2.0, 1.0 ] );
var out = new Float64Array( 2 );

var v = cdiv.strided( z1, 1, 0, z2, 1, 0, out, 1, 0 );
// returns <Float64Array>[ 5.0, 3.0 ]

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

The function supports the following parameters:

  • z1: first complex number strided array view.
  • sz1: stride length for z1.
  • oz1: starting index for z1.
  • z2: second complex number strided array view.
  • sz2: stride length for z2.
  • oz2: starting index for z2.
  • out: output array.
  • so: stride length for out.
  • oo: starting index for out.

Examples

var Complex128Array = require( '@stdlib/array/complex128' );
var discreteUniform = require( '@stdlib/random/array/discrete-uniform' );
var logEachMap = require( '@stdlib/console/log-each-map' );
var cdiv = require( '@stdlib/complex/float64/base/div' );

// Generate arrays of random values:
var z1 = new Complex128Array( discreteUniform( 200, -50, 50 ) );
var z2 = new Complex128Array( discreteUniform( 200, -50, 50 ) );

// Perform element-wise division:
logEachMap( '(%s) / (%s) = %s', z1, z2, cdiv );

C APIs

Usage

#include "stdlib/complex/float64/base/div.h"

stdlib_base_complex128_div( z1, z2 )

Divides two double-precision complex floating-point numbers.

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

stdlib_complex128_t z1 = stdlib_complex128( -13.0, -1.0 );
stdlib_complex128_t z2 = stdlib_complex128( -2.0, 1.0 );

stdlib_complex128_t out = stdlib_base_complex128_div( z1, z2 );

double re = stdlib_complex128_real( out );
// returns 5.0

double im = stdlib_complex128_imag( out );
// returns 3.0

The function accepts the following arguments:

  • z1: [in] stdlib_complex128_t input value.
  • z2: [in] stdlib_complex128_t input value.
stdlib_complex128_t stdlib_base_complex128_div( const stdlib_complex128_t z1, const stdlib_complex128_t z2 );

Examples

#include "stdlib/complex/float64/base/div.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_complex128_div( v, v );
        stdlib_complex128_reim( y, &re, &im );
        printf( "cdiv(z, z) = %lf + %lfi\n", re, im );
    }
}

References

  • Smith, Robert L. 1962. "Algorithm 116: Complex Division." Commun. ACM 5 (8). New York, NY, USA: ACM: 435. doi:10.1145/368637.368661.
  • Stewart, G. W. 1985. "A Note on Complex Division." ACM Trans. Math. Softw. 11 (3). New York, NY, USA: ACM: 238–41. doi:10.1145/214408.214414.
  • Priest, Douglas M. 2004. "Efficient Scaling for Complex Division." ACM Trans. Math. Softw. 30 (4). New York, NY, USA: ACM: 389–401. doi:10.1145/1039813.1039814.
  • Baudin, Michael, and Robert L. Smith. 2012. "A Robust Complex Division in Scilab." arXiv abs/1210.4539 [cs.MS] (October): 1–25. <https://arxiv.org/abs/1210.4539>.

See Also