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.
Warning
This function is
currently not documented; only the argument list is
available.
Note: This function is not
implemented on Windows platforms.