expm1
(PHP 4 >= 4.0.7, 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 $arg
)
WarningThis function is
EXPERIMENTAL. The behaviour of this function, its name, and
surrounding documentation may change without notice in a future release of PHP.
This function should be used at your own risk.
expm1() returns the equivalent to
'exp(arg
) - 1' computed in a way that is
accurate even if the value of arg
is near zero,
a case where 'exp (arg
) - 1' would be
inaccurate due to subtraction of two numbers that are nearly equal.
Parameters
-
arg
-
The argument to process
Return Values
'e' to the power of arg
minus one
exp
