Euler's number.
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> The mathematical constant [_e_][e].
``bash`
npm install @stdlib/constants-float64-e
`javascript`
var E = require( '@stdlib/constants-float64-e' );
#### E
The mathematical constant [_e_][e], also known as Euler's number or Napier's constant. [_e_][e] is the base of the natural logarithm.
`javascript`
var bool = ( E === 2.718281828459045 );
// returns true
`javascript
var E = require( '@stdlib/constants-float64-e' );
console.log( E );
// => 2.718281828459045
`
*
`c`
#include "stdlib/constants/float64/e.h"
#### STDLIB_CONSTANT_FLOAT64_E
Macro for Euler's 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.
For more information on the project, filing bug reports and feature requests, and guidance on how to develop [stdlib][stdlib], see the main project [repository][stdlib].
#### Community
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---
See [LICENSE][stdlib-license].
Copyright © 2016-2026. The Stdlib [Authors][stdlib-authors].
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[stdlib]: https://github.com/stdlib-js/stdlib
[stdlib-authors]: https://github.com/stdlib-js/stdlib/graphs/contributors
[umd]: https://github.com/umdjs/umd
[es-module]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Modules
[deno-url]: https://github.com/stdlib-js/constants-float64-e/tree/deno
[deno-readme]: https://github.com/stdlib-js/constants-float64-e/blob/deno/README.md
[umd-url]: https://github.com/stdlib-js/constants-float64-e/tree/umd
[umd-readme]: https://github.com/stdlib-js/constants-float64-e/blob/umd/README.md
[esm-url]: https://github.com/stdlib-js/constants-float64-e/tree/esm
[esm-readme]: https://github.com/stdlib-js/constants-float64-e/blob/esm/README.md
[branches-url]: https://github.com/stdlib-js/constants-float64-e/blob/main/branches.md
[stdlib-license]: https://raw.githubusercontent.com/stdlib-js/constants-float64-e/main/LICENSE
[e]: https://en.wikipedia.org/wiki/E_%28mathematical_constant%29