php 한글 메뉴얼 도움말 검색 사이트 Returns exp(number) - 1, computed in a way that is accurate even [function.expm1]

설명

float expm1 ( float $arg )

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.

인수

arg: The argument to process

반환값

'e' to the power of arg minus one

변경점

버전	설명
5.3.0	This function is now available on all platforms

참고

log1p() - Returns log(1 + number), computed in a way that is accurate even when the value of number is close to zero
exp() - e의 누승을 계산