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Salathe · 05-19-2008, 12:31 PM

To find the number of rounds from players, it looks like you could use the log2 value. In PHP we don't have this function available (though it is in C) but we do have a more general log function which can take a variable base value and for our purposes that base should be 2.

To quote the PHP Manual page:

float log ( float $arg [, float $base ] )

If the optional base parameter is specified, log() returns logbase arg , otherwise log() returns the natural logarithm of arg.

In practice, we can use it like so:

PHP Code:


			
$players  = 64;

$brackets = ($players * 2) - 1;     // 127

$rounds   = (int) log($players, 2); // 6

05-19-2008, 12:31 PM	#2 (permalink)
Salathe Moderateur Join Date: Apr 2007 Posts: 1,393 Thanks: 5	To find the number of rounds from players, it looks like you could use the `log2` value. In PHP we don't have this function available (though it is in C) but we do have a more general `log` function which can take a variable base value and for our purposes that base should be 2. To quote the PHP Manual page: `float log ( float $arg [, float $base ] )` If the optional base parameter is specified, log() returns logbase arg , otherwise log() returns the natural logarithm of arg. In practice, we can use it like so: PHP Code: `$players = 64; $brackets = ($players * 2) - 1; // 127 $rounds = (int) log($players, 2); // 6`