fmod
    (PHP 4 >= 4.2.0)
fmod -- Returns the floating point remainder (modulo) of the division     of the arguments
Description
float 
fmod ( float x, float y)
     Returns the floating point remainder of dividing the dividend      (x) by the divisor (y).      The reminder (r) is defined as: x = i * y + r, for       some integer i. If y is      non-zero, r has the same sign as      x and a magnitude less than the magnitude of      y.     
     
| Example 1. Using fmod() | <?php
$x = 5.7;
$y = 1.3;
$r = fmod($x, $y);
// $r equals 0.5, because 4 * 1.3 + 0.5 = 5.7
 ?> | 
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