php man page for mt_getrandmax

MT_GETRANDMAX(3)							 1							  MT_GETRANDMAX(3)

mt_getrandmax - Show largest possible random value

SYNOPSIS
       int mt_getrandmax (void	)

DESCRIPTION
	Returns the maximum value that can be returned by a call to mt_rand(3).

RETURN VALUES
	Returns  the  maximum random value returned by a call to mt_rand(3) without arguments, which is the maximum value that can be used for its
       $max parameter without the result being scaled up (and therefore less random).

EXAMPLES
       Example #1

	      Calculate a random floating-point number

	      <?php
	      function randomFloat($min = 0, $max = 1) {
		  return $min + mt_rand() / mt_getrandmax() * ($max - $min);
	      }

	      var_dump(randomFloat());
	      var_dump(randomFloat(2, 20));
	      ?>

	      The above example will output something similar to:

	      float(0.91601131712832)
	      float(16.511210331931)

SEE ALSO
       mt_rand(3), mt_srand(3), getrandmax(3).

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