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# expm1

(PHP 4 >= 4.1.0, PHP 5)

expm1 -- Returns exp(number) - 1, computed in a way that is accurate even when the value of number is close to zero

## Description

float expm1 ( float number )

Warning
This function is EXPERIMENTAL. The behaviour of this function, the name of this function, and anything else documented about this function may change without notice in a future release of PHP. Use this function at your own risk.

expm1() returns the equivalent to 'exp(number) - 1' computed in a way that is accurate even if the value of number is near zero, a case where 'exp (number) - 1' would be inaccurate due to subtraction of two numbers that are nearly equal.

> Note: This function is not implemented on Windows platforms.

See also log1p() and exp().

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