Question

Working in PHP, assume you have an associative array:

'Monday' => 'mon'
'Tuesday' => 'tue'
'Wednesday' => 'wed'
'Thursday' => 'thur'
'Friday' => 'fri'
'Saturday' => 'sat'
'Sunday' => 'sun'

How could you perform a “circular” array shift? Say shifting things so that the array starts with Wednesday, and proceeds through all 7 days, ending with Tuesday?

An important note: I need to do this by key, as I have other code determining what day the shift needs to start at.

Answer 1

No looping required

 $arr=array('Monday' => 'mon',
'Tuesday' => 'tue',
'Wednesday' => 'wed',
'Thursday' => 'thur',
'Friday' => 'fri',
'Saturday' => 'sat',
'Sunday' => 'sun');
//say your start is wednesday
$key = array_search("Wednesday",array_keys($arr));
$output1 = array_slice($arr, $key); 
$output2 = array_slice($arr, 0,$key); 
$new=array_merge($output1,$output2);
print_r($new);