log1p

(PHP 4 >= 4.1.0, PHP 5, PHP 7)

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

Description

log1p ( float $number ) : float

log1p() returns log(1 + number) computed in a way that is accurate even when the value of number is close to zero. log() might only return log(1) in this case due to lack of precision.

Parameters

number

The argument to process

Return Values

log(1 + number)

See Also

  • expm1() - Returns exp(number) - 1, computed in a way that is accurate even when the value of number is close to zero
  • log() - Natural logarithm
  • log10() - Base-10 logarithm

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Licensed under the Creative Commons Attribution License v3.0 or later.
https://www.php.net/manual/en/function.log1p.php