compare times with hundredths in php

Question

I try to compare two swim times in php. They are like HH:MM:SS.XX (XX are hundreths). I get them as string and i want to find out which swimmer is faster. I tryed to convert them using strtotime(). It works with hours, minutes and seconds but it ignores hundreths. Here is my code for better explanation:

$novy = strtotime($input1); 
$stary = strtotime($input2);
if($novy < $stary){
   //change old(stary) to new(novy)
}

If $input1 is 00:02:14.31 and $input2 is 00:02:14.32 both $novy and $stary are 1392850934. I read some solution to similar problem in javascript but I can`t use it, this must be server-side. Thank you for help.

Answer 1

If the format is really HH:MM:SS.XX (ie: with leading 0's), you can just sort them alphabetically:

<?php
$input1 = '00:02:14.31';
$input2 = '00:02:14.32';
if ($input1 < $input2) {
    echo "1 faster\n";
} else {
    echo "2 faster\n";
}

It prints 1 faster

Answer 2

If you use date_create_from_format you can specify the exact date format for php to convert the string representations to:

<?php
$input1 = '00:02:14.31';
$input2 = '00:02:14.32';
$novy = date_create_from_format('H:i:s.u', $input1);
$stary = date_create_from_format('H:i:s.u',$input2);
if ($novy < $stary) {
    echo "1 shorter\n";
} else {
    echo "2 longer\n";
}

Recommended reading: http://ie2.php.net/datetime.createfromformat

Answer 3

You could write some conditional logic to test if HH::MM::SS are identical, then simply compare XX, else use the strtotime() function that you are already using

Answer 4

You are working with durations, not dates. PHP's date and time functions aren't really of any help here. You should parse the string yourself to get a fully numeric duration:

$time = '00:02:14.31';

sscanf($time, '%d:%d:%d.%d', $hours, $minutes, $seconds, $centiseconds);
$total = $centiseconds
       + $seconds * 100
       + $minutes * 60 * 100
       + $hours * 60 * 60 * 100;

var_dump($total);

The total is in centiseconds (100th of a second, the scale of your original input). Multiply/divide by other factors to get in others scales, as needed.