This is probably going to sound strange, but I like to try to think outside the box (buzzphrase!) and hit things at odd angles.
Would someone care to test (or already know) the performance difference between a "for" loop and a "foreach" loop?
Or the performance difference over many iterations of "if (something == somethingelse)" versus "if (true)"?
Two examples to test:
<?php
$arr = array_fill(0, 999999, 'echo \"test standard\";');
$arr[100] = 'echo \"test special\";';
foreach ($arr as $value) {
eval($value);
}
?>
or....
<?php
$arr = array_fill(0, 999999, true);
$arr[100] = false;
foreach ($arr as $value) {
if ($value) {
// do standard
} else {
// do special
}
}
?>
I'd be curious to see the benchmarks. I wonder if a "if()" versus doing the value check in a "for" statement are different speed-wise.. I'm wondering how much "eval()" slows it down.. and I'm wondering if "if (value == value2)" is slower than "if (true)".
Probably other offbeat ways of doing something like this too.
-TG
= = = Original message = = =
Hi everyone
Quick question:
If I have such a loop:
<?
for($i=0;$i<1000000;$i++)
if($i==100)
// do something special for this occurence
// do something standard
?>
In this case it seems such a waste that the if() statement is done 999999
times when it's not needed. Is there any obvious trick that I am missing?
I'm not sure how taxing a simple if() statement is on a server, maybe it's
negligible, or is it something to worry about?
Something which I'd prefer NOT to do:
<?
for($i=0;$i<100;$i++)
// do something standard
// do something special for $i = 100
for($i=101;$i<1000000;$i++)
// do something standard
?>
as I would have have to either keep two copies of the code or write a
function just for this purpose, which hardly seems worth it.
Thanks to anyone who takes the time to think about my question and/or
respond.
Best wishes,
Steve McGill
___________________________________________________________
Sent by ePrompter, the premier email notification software.
Free download at http://www.ePrompter.com.
--
PHP General Mailing List (http://www.php.net/)
To unsubscribe, visit: http://www.php.net/unsub.php
