Shawn McKenzie schreef:
> Shawn McKenzie wrote:
...
>>> Not tested:
no shit.
>>> function time_sort($a, $b)
>>> {
>>> if (strtotime($a) == strtotime($b)) {
>>> return 0;
>>> }
>>> return (strtotime($a) < strtotime($b) ? -1 : 1;
>>> }
>>>
>>> usort($time, "time_sort");
>>>
>> Well, I just thought, since the strtotime() uses the current timestamp
>> to calculate the new timestamp, if you only give it a time then the
>> returned timestamp is today's date with the new time you passed. If you
>> had a large array and the callback started at 23:59:59 then you could
>> end up with some times from the date it started and some from the next
>> day, which of course would not be sorted correctly with respect to times
>> only. So, this might be better (not tested):
>>
ditto (as in nice syntax error).
>>
>> function time_sort($a, $b)
>> {
>> static $now = time();
>>
>> if (strtotime($a, $now) == strtotime($b, $now)) {
>> return 0;
>> }
>> return (strtotime($a, $now) < strtotime($b, $now) ? -1 : 1;
>> }
>>
>>
> Your best bet above.
and G.W.Bush is a socialist.
>
I did a little test, the ultra-fast version offered by McKenzie
is really great as long as your array of time strings aren't ever
going to be longer than say 3-4 items (with the caveat that you
don't use a second argument to strtotime() ... if you do then
even with 3 items it's substantially slower).
for any reasonable number of items my tests show tedd's version
pisses on McKenzies from a great height (note that I actually
optimized Mckenzies variant by halfing the number of calls to
strtotime()).
I added a third variant, as a sort of control, which runs pretty
much on par with tedd's version but uses rather less LOC
(tedd you might like it as a little example of using array_multisort(),
i.e. a way of avoiding writing the double foreach loop in this case)
tedd's variant: sortTime1()
McKenzie's variant: sortTime2()
my variant: sortTime3()
sample output from one of my test runs:
===============================================================
===============================================================
No. of array items = 3, no of iterations = 10000
-------
timeSort1() ran for 1.306011 seconds
timeSort2() ran for 1.337358 seconds
timeSort3() ran for 1.742724 seconds
No. of array items = 6, no of iterations = 10000
-------
timeSort1() ran for 2.647697 seconds
timeSort2() ran for 2.475791 seconds
timeSort3() ran for 7.268916 seconds
No. of array items = 9, no of iterations = 10000
-------
timeSort1() ran for 3.891894 seconds
timeSort2() ran for 3.960463 seconds
timeSort3() ran for 18.440713 seconds
the test script:
===============================================================
===============================================================
<?php
// TEST
ini_set("date.timezone", "Europe/Amsterdam");
$iter = 10000;
$time = array(
array("1:30pm", "7:30am", "12:30pm"),
array("1:30pm", "7:30am", "12:30pm", "4:45pm", "8:15am", "11:00pm"),
array("1:30pm", "7:30am", "12:30pm", "4:45pm", "8:15am", "11:00pm", "4:30am", "6:45am", "12:00pm"),
);
foreach ($time as $t)
testIt($t, $iter);
// FUNCS
function sortTime1($in_times)
{
$time = array();
foreach ($in_times as $t)
$time[] = strtotime($t);
sort($time);
$sort_time = array();
foreach ($time as $t)
$sort_time[] = date("g:ia", $t);
return $sort_time;
}
function timeSort2($in)
{
static $time = null;
if (!$time)
$time = time();
$now = array_fill(0, count($in), $time);
$out = array_map("strtotime", $in, $now);
array_multisort($out, SORT_NUMERIC, SORT_ASC, $in);
return $in;
}
function timeSort3($a, $b)
{
static $now = null;
if (!$now)
$now = time();
$a = strtotime($a, $now);
$b = strtotime($b, $now);
if ($a == $b)
return 0;
return $a < $b ? -1 : 1;
}
function testIt($time, $iter)
{
echo "\nNo. of array items = ", count($time), ", no of iterations = $iter\n-------\n";
$s = microtime(true);
for ($i = 0; $i < $iter; $i++)
timeSort2($time);
$e = microtime(true);
echo "timeSort1() ran for ".round($e-$s, 6)." seconds \n";
$s = microtime(true);
for ($i = 0; $i < $iter; $i++)
timeSort2($time);
$e = microtime(true);
echo "timeSort2() ran for ".round($e-$s, 6)." seconds \n";
$s = microtime(true);
for ($i = 0; $i < $iter; $i++)
usort($time, "timeSort3");
$e = microtime(true);
echo "timeSort3() ran for ".round($e-$s, 6)." seconds \n";
}
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