questions on sort array by time in php

Question

---array $points----

Array
    (
        [0] => Array
            (
                [0] => 2011-10-02 05:30:00
                [1] =&         


        

Answer 1

What you want to do is (basic idea):

foreach($points as $key=>$val){
     $time[$val[1]] = $val[0]; // $time will be an array of [ point => time ] pairs
}
asort( $time ); // sorts the array and maintains indexes

After this you have an array of point => time pairs, sorted by time. To get just the points, for instance do

$points = array_keys( $time );