Size (in bytes) of a double-precision floating-point number.
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> Size (in bytes) of a [double-precision floating-point number][ieee754].
``bash`
npm install @stdlib/constants-float64-num-bytes
`javascript`
var FLOAT64_NUM_BYTES = require( '@stdlib/constants-float64-num-bytes' );
#### FLOAT64_NUM_BYTES
Size (in bytes) of a [double-precision floating-point number][ieee754].
`javascript`
var bool = ( FLOAT64_NUM_BYTES === 8 );
// returns true
`javascript
var FLOAT64_NUM_BYTES = require( '@stdlib/constants-float64-num-bytes' );
console.log( FLOAT64_NUM_BYTES );
// => 8
`
*
`c`
#include "stdlib/constants/float64/num_bytes.h"
#### STDLIB_CONSTANT_FLOAT64_NUM_BYTES
Macro for the size (in bytes) of a [double-precision floating-point number][ieee754].
*
- [@stdlib/constants-float16/num-bytes][@stdlib/constants/float16/num-bytes]: size (in bytes) of a half-precision floating-point number.
- [@stdlib/constants-float32/num-bytes][@stdlib/constants/float32/num-bytes]: size (in bytes) of a single-precision floating-point number.
*
This package is part of [stdlib][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.
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[@stdlib/constants/float16/num-bytes]: https://www.npmjs.com/package/@stdlib/constants-float16-num-bytes
[@stdlib/constants/float32/num-bytes]: https://www.npmjs.com/package/@stdlib/constants-float32-num-bytes