expm1

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

Description

float expm1(float $num)

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

Parameters

num

The argument to process

Return Values

e to the power of num, minus one.

See Also

  • log1p
  • exp