log
(PHP 4, PHP 5, PHP 7, PHP 8)
log — Natural logarithm
Description
log(float $num, float $base = M_E): floatIf the optional base parameter is specified, log() returns logbase num, otherwise log() returns the natural logarithm of num.
Parameters
num-
The value to calculate the logarithm for
base-
The optional logarithmic base to use (defaults to 'e' and so to the natural logarithm).
Return Values
The logarithm of num to base, if given, or the natural logarithm.
See Also
- log10() - Base-10 logarithm
- exp() - Calculates the exponent of e
- pow() - Exponential expression
- error_log() - Send an error message to the defined error handling routines
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Licensed under the Creative Commons Attribution License v3.0 or later.
https://www.php.net/manual/en/function.log.php