stdlib-js/math-base-special-exp

Natural exponential function.

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exp

Natural exponential function.

The natural exponential function is defined as

$$y = e^x$$

where e is Euler's number.

Installation

npm install @stdlib/math-base-special-exp

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 exp = require( '@stdlib/math-base-special-exp' );

exp( x )

Evaluates the natural exponential function.

var v = exp( 4.0 );
// returns ~54.5982

v = exp( -9.0 );
// returns ~1.234e-4

v = exp( 0.0 );
// returns 1.0

v = exp( NaN );
// returns NaN

Examples

var randu = require( '@stdlib/random-base-randu' );
var exp = require( '@stdlib/math-base-special-exp' );

var x;
var i;

for ( i = 0; i < 100; i++ ) {
    x = (randu()*100.0) - 50.0;
    console.log( 'e^%d = %d', x, exp( x ) );
}

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C APIs

Usage

#include "stdlib/math/base/special/exp.h"

stdlib_base_exp( x )

Evaluates the natural exponential function.

double out = stdlib_base_exp( 4.0 );
// returns ~54.5982

out = stdlib_base_exp( -9.0 );
// returns ~1.234e-4

The function accepts the following arguments:

• x: [in] double input value.

double stdlib_base_exp( const double x );

Examples

#include "stdlib/math/base/special/exp.h"
#include <stdlib.h>
#include <stdio.h>

int main( void ) {
    double x;
    double v;
    int i;
    
    for ( i = 0; i < 100; i++ ) {
        x = ( (double)rand() / (double)RAND_MAX ) * 100.0;
        v = stdlib_base_exp( x );
        printf( "e^%lf = %lf\n", x, v );
    }
}

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See Also

• @stdlib/math-base/special/exp10: base 10 exponential function.
• @stdlib/math-base/special/exp2: base 2 exponential function.
• @stdlib/math-base/special/expm1: compute exp(x) - 1.
• @stdlib/math-base/special/ln: evaluate the natural logarithm of a double-precision floating-point number.

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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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Copyright

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