log1p
(PHP 4 >= 4.1.0)
log1p -- Returns log(1 + number), computed in a way that accurate even when the val ue of number is close to zeroDescription
float log1p ( 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. | 
