Efficient way to sort an array? - php

Question

I have an array of variabel length, containing events sorted by startdate, looking like this:
Array
(
[0] => stdClass Object
(
[id] => 1978
[date] => 2012-09-29
)
[1] => stdClass Object
(
[id] => 1979
[date] => 2012-10-14
)
...etc....
I need to make a function that takes one of the event, and puts in the middle of a new array with a length of exactly seven, and puts the event's neighbours on each side.
So if event 5 passed to the function, the output should be:
[2][3][4][5][6][7][8]
If the first event is passed to the function, and the original amount of events is 12, the output should be:
[10][11][12][1][2][3][4]
If the orignal amount of events is 6, and the fifth event is passed, the output should be:
[2][3][4][5][6][1][]
So the list of events should always "wrap around" in the new array and fill it up as much as possible.
I have hacked together a solution, that involves quite a bit of steps. I dont really like it, and it got me wondering:
How would this be done in the most efficient and elegant way?

Answer 1

You need to change the values in this codes
define('TO_SHOW',7); // number of items to show in your case it is 7
$selected = 1; //// which one you need need at center.
and your array;
Execute this and try :
<?php
define('TO_SHOW',7); // number of items to show in your case it is 7
function change_order($arry, $sel){
$arr_cnt = count($arry);
$shift_count = $arr_cnt - (ceil(TO_SHOW/2)-$sel);
for($i=0; $i<$shift_count; $i++){
array_push($arry, array_shift($arry));
}
return array_slice($arry, 0, TO_SHOW);
}
$arr = array(array(
"id" => 1,
"date" => 2012-09-29
),
array(
"id" => 2,
"date" => 2012-09-29
),
array(
"id" => 3,
"date" => 2012-09-29
),
array(
"id" => 4,
"date" => 2012-09-29
),
array(
"id" => 5,
"date" => 2012-09-29
),
array(
"id" => 6,
"date" => 2012-09-29
),
array(
"id" => 7,
"date" => 2012-09-29
),
array(
"id" => 8,
"date" => 2012-09-29
),
array(
"id" => 9,
"date" => 2012-09-29
),
array(
"id" => 10,
"date" => 2012-09-29
),
array(
"id" => 11,
"date" => 2012-09-29
),
array(
"id" => 12,
"date" => 2012-09-29
),
array(
"id" => 13,
"date" => 2012-09-29
),
array(
"id" => 14,
"date" => 2012-09-29
)
);
$selected = 1; //// centre one
$test = change_order($arr, $selected);
echo "<pre>";
print_r($test);
?>