real

Return the real component of a double-precision complex floating-point number.

Usage

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

real( z )

Returns the real component of a double-precision complex floating-point number.

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

var z = new Complex128( 5.0, 3.0 );
var re = real( z );
// returns 5.0

Examples

var Complex128 = require( '@stdlib/complex/float64/ctor' );
var discreteUniform = require( '@stdlib/random/base/discrete-uniform' );
var filledarrayBy = require( '@stdlib/array/filled-by' );
var real = require( '@stdlib/complex/float64/real' );

function random() {
    return new Complex128( discreteUniform( -10, 10 ), discreteUniform( -10, 10 ) ); // eslint-disable-line max-len
}

// Generate an array of random complex numbers:
var x = filledarrayBy( 100, 'complex128', random );
// returns <Complex128Array>

// Retrieve the real component of each complex number...
var z;
var i;
for ( i = 0; i < x.length; i++ ) {
    z = x.get( i );
    console.log( 'real(%s) = %d', z.toString(), real( z ) );
}

C APIs

Usage

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

stdlib_complex128_real( z )

Returns the real component of a double-precision complex floating-point number.

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

stdlib_complex128_t z = stdlib_complex128( 5.0, 2.0 );

// ...

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

The function accepts the following arguments:

z: [in] stdlib_complex128_t double-precision complex floating-point number.

double stdlib_complex128_real( const stdlib_complex128_t z );

Examples

#include "stdlib/complex/float64/real.h"
#include "stdlib/complex/float64/ctor.h"
#include <stdio.h>

int main( void ) {
    const stdlib_complex128_t x[] = {
        stdlib_complex128( 5.0, 2.0 ),
        stdlib_complex128( -2.0, 1.0 ),
        stdlib_complex128( 0.0, -0.0 ),
        stdlib_complex128( 0.0/0.0, 0.0/0.0 )
    };

    int i;
    for ( i = 0; i < 4; i++ ) {
        printf( "real(v) = %lf\n", stdlib_complex128_real( x[ i ] ) );
    }
}