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<?php /* @link http://stackoverflow.com/q/15931375/2261774 */ error_reporting(~0); $array = array( array('Jan 2010', 65.75), array('Jan 2010', 211.05), array('Jan 2010', 582.7), array('Feb 2010', 136.3), array('Feb 2010', 215.32), array('Feb 2010', 413.9), array('Mar 2010', 156.35), array('Mar 2010', 210.54), array('Mar 2010', 585.15), array('Apr 2010', 126.1), array('Apr 2010', 255.47), array('Apr 2010', 329.1), array('May 2010', 109), array('May 2010', 170), array('May 2010', 716.7), ); foreach($array as $key => &$entry) { list($month, $value) = $entry; if (isset($ptr[$month])) { $ptr[$month][] = $value; unset($array[$key]); } else { $ptr[$month] = &$entry; } } unset($ptr); print_r($array);
Output for 5.2.2 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.24 - 5.5.35, 5.6.7 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.20, 7.2.0 - 7.2.33, 7.3.12 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
Array ( [0] => Array ( [0] => Jan 2010 [1] => 65.75 [2] => 211.05 [3] => 582.7 ) [3] => Array ( [0] => Feb 2010 [1] => 136.3 [2] => 215.32 [3] => 413.9 ) [6] => Array ( [0] => Mar 2010 [1] => 156.35 [2] => 210.54 [3] => 585.15 ) [9] => Array ( [0] => Apr 2010 [1] => 126.1 [2] => 255.47 [3] => 329.1 ) [12] => Array ( [0] => May 2010 [1] => 109 [2] => 170 [3] => 716.7 ) )
Output for 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.1
Array ( [0] => Array ( [0] => Jan 2010 [1] => 65.75 [2] => 211.05 [3] => 582.7 ) [3] => Array ( [0] => Feb 2010 [1] => 136.3 ) [6] => Array ( [0] => Mar 2010 [1] => 156.35 ) [9] => Array ( [0] => Apr 2010 [1] => 126.1 ) [12] => Array ( [0] => May 2010 [1] => 109 ) )
Output for 4.4.2 - 4.4.9
Parse error: syntax error, unexpected '&', expecting T_VARIABLE or '$' in /in/pgaoh on line 24
Process exited with code 255.
Output for 4.3.0 - 4.3.1, 4.3.5 - 4.3.11, 4.4.0 - 4.4.1
Parse error: parse error, unexpected '&', expecting T_VARIABLE or '$' in /in/pgaoh on line 24
Process exited with code 255.
Output for 4.3.2 - 4.3.4
Parse error: parse error, expecting `T_VARIABLE' or `'$'' in /in/pgaoh on line 24
Process exited with code 255.

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