Name

Math.log() — compute a natural logarithm

Synopsis

Math.log(x)

Arguments

x

Any numeric value or expression greater than zero.

Returns

The natural logarithm of x.

Description

Math.log() computes log e x, the natural logarithm of its argument. The argument must be greater than zero.

You can compute the base-10 and base-2 logarithms of a number with these formulas:

log10x  = log10e · logex
log2x  = log2e · logex

These formulas translate into the following JavaScript functions:

function log10(x) { return Math.LOG10E * Math.log(x); }
function log2(x) { return  Math.LOG2E * Math.log(x); }

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