@stdlib/number-float64-base-set-high-word
    TypeScript icon, indicating that this package has built-in type declarations

    0.0.5 • Public • Published

    Set High Word

    NPM version Build Status Coverage Status dependencies

    Set the more significant 32 bits of a double-precision floating-point number.

    Installation

    npm install @stdlib/number-float64-base-set-high-word

    Usage

    var setHighWord = require( '@stdlib/number-float64-base-set-high-word' );

    setHighWord( x, high )

    Sets the more significant 32 bits (higher order word) of a double-precision floating-point number x to a bit sequence represented by an unsigned 32-bit integer high. The returned double will have the same less significant 32 bits (lower order word) as x.

    var high = 5 >>> 0; // => 0 00000000000 00000000000000000101
    
    var y = setHighWord( 3.14e201, high ); // => 0 00000000000 0000000000000000010110010011110010110101100010000010
    // returns 1.18350528745e-313
    
    var PINF = require( '@stdlib/constants-float64-pinf' ); // => 0 11111111111 00000000000000000000 00000000000000000000000000000000
    
    high = 1072693248 >>> 0; // => 0 01111111111 00000000000000000000
    
    // Set the higher order bits of `+infinity` to return `1`:
    y = setHighWord( PINF, high ); // => 0 01111111111 0000000000000000000000000000000000000000000000000000
    // returns 1.0

    Examples

    var pow = require( '@stdlib/math-base-special-pow' );
    var round = require( '@stdlib/math-base-special-round' );
    var randu = require( '@stdlib/random-base-randu' );
    var MAX_UINT32 = require( '@stdlib/constants-uint32-max' );
    var setHighWord = require( '@stdlib/number-float64-base-set-high-word' );
    
    var high;
    var frac;
    var exp;
    var x;
    var y;
    var i;
    
    // Generate a random double-precision floating-point number:
    frac = randu() * 10.0;
    exp = -round( randu() * 323.0 );
    x = frac * pow( 10.0, exp );
    
    // Replace the higher order word of `x` to generate new random numbers having the same lower order word...
    for ( i = 0; i < 100; i++ ) {
        high = round( randu()*MAX_UINT32 );
        y = setHighWord( x, high );
        console.log( 'x: %d. new high word: %d. y: %d.', x, high, y );
    }

    C APIs

    Installation

    npm install @stdlib/number-float64-base-set-high-word

    Usage

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

    stdlib_base_float64_set_high_word( high, *x )

    Sets the more significant 32 bits of a double-precision floating-point number.

    #include <stdint.h>
    
    uint32_t high = 1074339512;
    double x = 0.0;
    
    stdlib_base_float64_set_high_word( high, &x );

    The function accepts the following arguments:

    • high: [in] uint32_t higher order word.
    • x: [in-out] double* reference to (and destination for) a double-precision floating-point number.
    void stdlib_base_float64_set_high_word( const uint32_t high, double *x );

    Examples

    #include "stdlib/number/float64/base/set_high_word.h"
    #include <stdint.h>
    #include <stdio.h>
    
    int main() {
        uint32_t high[] = { 1074339512, 1074339513, 1074339514, 1074339515 };
        double x = 3.14;
    
        int i;
        for ( i = 0; i < 4; i++ ) {
            stdlib_base_float64_set_high_word( high[ i ], &x );
            printf( "high: %u => %lf\n", high[ i ], x );
        }
    }

    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

    Chat


    License

    See LICENSE.

    Copyright

    Copyright © 2016-2021. The Stdlib Authors.

    Install

    npm i @stdlib/number-float64-base-set-high-word

    Homepage

    stdlib.io

    DownloadsWeekly Downloads

    3,055

    Version

    0.0.5

    License

    Apache-2.0

    Unpacked Size

    58.9 kB

    Total Files

    17

    Last publish

    Collaborators

    • stdlib-bot
    • kgryte
    • planeshifter
    • rreusser