README

Logarithm

$NPM version$ $Build Status$ $Coverage Status$ $dependencies$

Compute the base b logarithm.

Installation

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

Usage

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

log( x, b )

Computes the base b logarithm of x.

var v = log( 100.0, 10.0 );
// returns 2.0

v = log( 16.0, 2.0 );
// returns 4.0

v = log( 5.0, 1.0 );
// returns Infinity

For negative x or b, the logarithm is not defined.

var v = log( -4.0, 1.0 );
// returns NaN

v = log( 2.0, -4.0 );
// returns NaN

Examples

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

var b;
var x;
var i;

for ( i = 0; i < 100; i++ ) {
    x = round( randu() * 100.0 );
    b = round( randu() * 5.0 );
    console.log( 'log( %d, %d ) = %d', x, b, log( x, b ) );
}

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

License

See LICENSE.

@stdlib/math-base-special-log

Usage no npm install needed!