@stdlib/number-float64-base-get-high-word

What is @stdlib/number-float64-base-get-high-word?

The @stdlib/number-float64-base-get-high-word package provides a utility to extract the higher order word (most significant 32 bits) from a double-precision floating-point number (64-bit). This can be useful for low-level bit manipulation and analysis of floating-point numbers.

What are @stdlib/number-float64-base-get-high-word's main functionalities?

Extract High Word

This feature allows you to extract the high word from a given double-precision floating-point number. The high word is the most significant 32 bits of the 64-bit floating-point number.

const getHighWord = require('@stdlib/number-float64-base-get-high-word');
const highWord = getHighWord(3.14);
console.log(highWord); // Output will be the high word of the float64 number 3.14

Other packages similar to @stdlib/number-float64-base-get-high-word

bit-twiddle

The bit-twiddle package provides a variety of bit manipulation utilities, including functions to extract specific bits, set bits, and perform other low-level operations. While it offers a broader range of bit manipulation functions, it does not specifically focus on extracting the high word from a float64 number like @stdlib/number-float64-base-get-high-word.

README

High Word

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

Installation

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

Usage

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

getHighWord( x )

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

var w = getHighWord( 3.14e201 ); // => 01101001110001001000001011000011
// returns 1774486211

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 getHighWord = require( '@stdlib/number-float64-base-get-high-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 = getHighWord( x );
    console.log( 'x: %d. high word: %d.', x, w );
}

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C APIs

Usage

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

stdlib_base_float64_get_high_word( x, *high )

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

#include <stdint.h>

uint32_t high;
stdlib_base_float64_get_high_word( 3.14, &high );

The function accepts the following arguments:

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

void stdlib_base_float64_get_high_word( const double x, uint32_t *high );

Examples

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

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

    uint32_t high;
    int i;
    for ( i = 0; i < 4; i++ ) {
        stdlib_base_float64_get_high_word( x[ i ], &high );
        printf( "%lf => high: %u\n", x[ i ], high );
    }
}

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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

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License

See LICENSE.

Copyright

Copyright © 2016-2022. The Stdlib Authors.