Test: tail recurison

Is using tail-end recursion (where the recursion happens at the end of the function) any better?

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Result: Discarded

The test labeled "normal recursion" was the faster by 0.1113 seconds, (9.046% faster)

normal recursion 100%

tail recursion 90.954%

The normal recursion test took 1.1187 seconds.
The tail recursion test took 1.23 seconds.

Nitty-Gritty

Each test case ran 20 random code order iterations consisting of 279,247 loops for a total of 5,584,940 runs.

Line execution difference (0.000020) milliseconds.
Avg difference (5.564) milliseconds per 279,247 loops.
Total difference 111.27 milliseconds for 5,584,940 loops

The iteration variablity for Code 1 was (6.2016) milliseconds and Code 2 was (12.1519) milliseconds. The lower and the closer together there values are the more accurate the results are.

Code

The first test, "normal recursion", was:

/*
function recurse_tail($i, $inside)
{
	$data = '<div>' . $inside . '</div>';

	if ($i <= 0)
		return $data;
	else
		return recurse_tail($i - 1, $data);
}
*/

$result = recurse_tail(200, '');

The second test, "tail recursion", was:

/*
function recurse_normal($i, $inside)
{
	$data = '<div>';
	if ($i <= 0)
		$data .= $inside;
	else
		$data .= recurse_normal($i - 1, $data);
	$data .= '</div>';

	return $data;
}
*/

$result = recurse_normal(200, '');

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