Low Word

Return an unsigned 32-bit integer corresponding to the less significant 32 bits of a double-precision floating-point number.

Installation

npm install @stdlib/number-float64-base-get-low-word

Usage

var getLowWord = require( '@stdlib/number-float64-base-get-low-word' );

getLowWord( x )

Returns an unsigned 32-bit integer corresponding to the less significant 32 bits of a double-precision floating-point number.

var w = getLowWord( 3.14e201 ); // => 10010011110010110101100010000010
// returns 2479577218

Examples

var floor = require( '@stdlib/math-base-special-floor' );
var randu = require( '@stdlib/random-base-randu' );
var pow = require( '@stdlib/math-base-special-pow' );
var getLowWord = require( '@stdlib/number-float64-base-get-low-word' );

var frac;
var exp;
var w;
var x;
var i;

for ( i = 0; i < 100; i++ ) {
    frac = randu() * 10.0;
    exp = -floor( randu()*324.0 );
    x = frac * pow( 10.0, exp );
    w = getLowWord( x );
    console.log( 'x: %d. low word: %d.', x, w );
}

C APIs

Usage

#include "stdlib/number/float64/base/get_low_word.h"

stdlib_base_float64_get_low_word( x, *low )

Extracts the unsigned 32-bit integer corresponding to the less significant 32 bits of a double-precision floating-point number.

#include <stdint.h>

uint32_t low;
stdlib_base_float64_get_low_word( 3.14, &low );

The function accepts the following arguments:

• x: [in] double input value.
• low: [out] uint32_t* destination for lower order word.

void stdlib_base_float64_get_low_word( const double x, uint32_t *low );

Examples

#include "stdlib/number/float64/base/get_low_word.h"
#include <stdint.h>
#include <stdio.h>

int main( void ) {
    double x[] = { 3.14, -3.14, 0.0, 0.0/0.0 };

    uint32_t low;
    int i;
    for ( i = 0; i < 4; i++ ) {
        stdlib_base_float64_get_low_word( x[ i ], &low );
        printf( "%lf => low: %u\n", x[ i ], low );
    }
}

See Also

• @stdlib/number-float64/base/get-high-word: return an unsigned 32-bit integer corresponding to the more significant 32 bits of a double-precision floating-point number.
• @stdlib/number-float64/base/set-high-word: set the more significant 32 bits of 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.