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muladd

Perform a multiply-add operation involving three single-precision complex floating-point numbers.

Usage

var muladd = require( '@stdlib/complex/float32/base/mul-add' );

muladd( alpha, x, y )

Performs a multiply-add operation involving three single-precision complex floating-point numbers.

var Complex64 = require( '@stdlib/complex/float32/ctor' );

var z1 = new Complex64( 5.0, 3.0 );
var z2 = new Complex64( -2.0, 1.0 );
var z3 = new Complex64( 7.0, -8.0 );

// Compute `alpha*x + y`:
var v = muladd( z1, z2, z3 );
// returns <Complex64>[ -6.0, -9.0 ]

The function supports the following parameters:

muladd.assign( ar, ai, xr, xi, yr, yi, out, strideOut, offsetOut )

Performs a multiply-add operation involving three single-precision complex floating-point numbers and assigns the results to an output strided array.

var Float32Array = require( '@stdlib/array/float32' );

var out = new Float32Array( 2 );
var v = muladd.assign( 5.0, 3.0, -2.0, 1.0, 7.0, -8.0, out, 1, 0 );
// returns <Float32Array>[ -6.0, -9.0 ]

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

The function supports the following parameters:

  • ar: real component of the first complex number.
  • ai: imaginary component of the first complex number.
  • xr: real component of the second complex number.
  • xi: imaginary component of the second complex number.
  • yr: real component of the third complex number.
  • yi: imaginary component of the third complex number.
  • out: output array.
  • strideOut: stride length for out.
  • offsetOut: starting index for out.

muladd.strided( alpha, sa, oa, x, sx, ox, y, sy, oy, out, so, oo )

Performs a multiply-add operation involving three single-precision complex floating-point numbers stored in real-valued strided array views and assigns results to a provided strided output array.

var Float32Array = require( '@stdlib/array/float32' );

var z1 = new Float32Array( [ 5.0, 3.0 ] );
var z2 = new Float32Array( [ -2.0, 1.0 ] );
var z3 = new Float32Array( [ 7.0, -8.0 ] );
var out = new Float32Array( 2 );

var v = muladd.strided( z1, 1, 0, z2, 1, 0, z3, 1, 0, out, 1, 0 );
// returns <Float32Array>[ -6.0, -9.0 ]

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

The function supports the following parameters:

  • alpha: first complex number strided array view.
  • sa: stride length for alpha.
  • oa: starting index for alpha.
  • x: second complex number strided array view.
  • sx: stride length for x.
  • ox: starting index for x.
  • y: third complex number strided array view.
  • sy: stride length for y.
  • oy: starting index for y.
  • out: output array.
  • so: stride length for out.
  • oo: starting index for out.

Examples

var Complex64Array = require( '@stdlib/array/complex64' );
var discreteUniform = require( '@stdlib/random/array/discrete-uniform' );
var logEachMap = require( '@stdlib/console/log-each-map' );
var muladd = require( '@stdlib/complex/float32/base/mul-add' );

// Generate arrays of random values:
var z1 = new Complex64Array( discreteUniform( 200, -50, 50 ) );
var z2 = new Complex64Array( discreteUniform( 200, -50, 50 ) );
var z3 = new Complex64Array( discreteUniform( 200, -50, 50 ) );

// Perform element-wise computation:
logEachMap( '( (%s) * (%s) ) + (%s) = %s', z1, z2, z3, muladd );

C APIs

Usage

#include "stdlib/complex/float32/base/mul_add.h"

stdlib_base_complex64_muladd( alpha, x, y )

Performs a multiply-add operation involving three single-precision complex floating-point numbers.

#include "stdlib/complex/float32/ctor.h"
#include "stdlib/complex/float32/real.h"
#include "stdlib/complex/float32/imag.h"

stdlib_complex64_t z1 = stdlib_complex64( 5.0f, 3.0f );
stdlib_complex64_t z2 = stdlib_complex64( -2.0f, 1.0f );
stdlib_complex64_t z3 = stdlib_complex64( 7.0f, -8.0f );

stdlib_complex64_t out = stdlib_base_complex64_muladd( z1, z2, z3 );

float re = stdlib_complex64_real( out );
// returns -6.0f

float im = stdlib_complex64_imag( out );
// returns -9.0f

The function accepts the following arguments:

  • alpha: [in] stdlib_complex64_t input value.
  • z1: [in] stdlib_complex64_t input value.
  • z2: [in] stdlib_complex64_t input value.
stdlib_complex64_t stdlib_base_complex64_muladd( const stdlib_complex64_t alpha, const stdlib_complex64_t x, const stdlib_complex64_t y );

Examples

#include "stdlib/complex/float32/base/mul_add.h"
#include "stdlib/complex/float32/ctor.h"
#include "stdlib/complex/float32/reim.h"
#include <stdio.h>

int main( void ) {
    const stdlib_complex64_t x[] = {
        stdlib_complex64( 3.14f, 1.5f ),
        stdlib_complex64( -3.14f, 1.5f ),
        stdlib_complex64( 0.0f, -0.0f ),
        stdlib_complex64( 0.0f/0.0f, 0.0f/0.0f )
    };

    stdlib_complex64_t v;
    stdlib_complex64_t y;
    float re;
    float im;
    int i;
    for ( i = 0; i < 4; i++ ) {
        v = x[ i ];
        stdlib_complex64_reim( v, &re, &im );
        printf( "z = %f + %fi\n", re, im );

        y = stdlib_base_complex64_muladd( v, v, v );
        stdlib_complex64_reim( y, &re, &im );
        printf( "z*z + z = %f + %fi\n", re, im );
    }
}