benchmarking-for-loop.php

<?php
header('Content-Type: text/plain');

/**
 * Build an array to loop.
 */
$time0 = microtime(true);
for($i=9999; $i>0; --$i)
{
	$values[] = null;
}
$time1 = microtime(true);
$diff1 = $time1 - $time0;

/**
 * Loop's internal logic uses count() in each loop
 */
for($i=0; $i<count($values); ++$i){}
$time2 = microtime(true);
$diff2 = $time2 - $time1;

/**
 * See next 2 lines! Rewrite the above one
 */
$total = count($values);
for($i=0; $i<$total; ++$i){}
$time3 = microtime(true);
$diff3 = $time3 - $time2;

/**
 * Sometimes, the difference is 0.
 */
$diff3 = $diff3?$diff3:0.00000000001;

#echo "\r\nValues Generation: ", $diff1;
echo "\r\nfor(\$i=0; \$i<count(\$values); ++\$i): ", $diff2;
echo "\r\nfor(\$i=0; \$i<\$total; ++\$i): ", $diff3;
echo sprintf("\r\nSpeed Gain: %0.2f times.", $diff2/$diff3);

/**
 * Values Generation: 0.15500903129578
 * for($i=0; $i<count($values); ++$i): 0.15700817108154
 * for($i=0; $i<$total; ++$i): 0.0060009956359863
 * Speed Gain: 26.16 times.
 */