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Float64

Base utilities for double-precision floating-point numbers.

Installation

npm install @stdlib/number-float64-base

Alternatively,

• To load the package in a website via a script tag without installation and bundlers, use the ES Module available on the esm branch (see README).
• If you are using Deno, visit the deno branch (see README for usage intructions).
• For use in Observable, or in browser/node environments, use the Universal Module Definition (UMD) build available on the umd branch (see README).

The branches.md file summarizes the available branches and displays a diagram illustrating their relationships.

To view installation and usage instructions specific to each branch build, be sure to explicitly navigate to the respective README files on each branch, as linked to above.

Usage

var ns = require( '@stdlib/number-float64-base' );

ns

Base utilities for double-precision floating-point numbers.

var o = ns;
// returns {...}

• assert: base double-precision floating-point number assert functions.
• exponent( x ): return an integer corresponding to the unbiased exponent of a double-precision floating-point number.
• fromBinaryString( bstr ): create a double-precision floating-point number from a literal bit representation.
• fromInt64Bytes( bytes, stride, offset ): convert a signed 64-bit integer byte array to a double-precision floating-point number.
• fromWords( high, low ): create a double-precision floating-point number from a higher order word and a lower order word.
• getHighWord( x ): return an unsigned 32-bit integer corresponding to the more significant 32 bits of a double-precision floating-point number.
• getLowWord( x ): return an unsigned 32-bit integer corresponding to the less significant 32 bits of a double-precision floating-point number.
• normalize( x ): return a normal number y and exponent exp satisfying x = y * 2^exp.
• setHighWord( x, high ): set the more significant 32 bits of a double-precision floating-point number.
• setLowWord( x, low ): set the less significant 32 bits of a double-precision floating-point number.
• signbit( x ): return a boolean indicating if the sign bit for a double-precision floating-point number is on (true) or off (false).
• toBinaryString( x ): return a string giving the literal bit representation of a double-precision floating-point number.
• float64ToFloat32( x ): convert a double-precision floating-point number to the nearest single-precision floating-point number.
• float64ToInt32( x ): convert a double-precision floating-point number to a signed 32-bit integer.
• float64ToInt64Bytes( x ): convert an integer-valued double-precision floating-point number to a signed 64-bit integer byte array according to host byte order (endianness).
• float64ToUint32( x ): convert a double-precision floating-point number to an unsigned 32-bit integer.
• toWords( x ): split a double-precision floating-point number into a higher order word and a lower order word.

Examples

var objectKeys = require( '@stdlib/utils-keys' );
var ns = require( '@stdlib/number-float64-base' );

console.log( objectKeys( ns ) );

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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 © 2016-2025. The Stdlib Authors.