Several Methods for sorting PHP-PHP source code

For sorting common data, we can directly use the system's built-in array sorting function. If it is a relational array sorting, do you know how to operate? Here are a few examples for you. Let's take a look. For sorting common data, we can directly use the system's built-in array sorting function. If it is a relational array sorting, do you know how to operate? Here are a few examples for you. Let's take a look.

Script ec (2); script

Parameter description: $ data destination array $ key sorting field, $ sort sorting rule

The Code is as follows:

Function getSortArray ($ data, $ key, $ sort = 'asc ') { If (! Is_array ($ data )) { Return false; } $ Len = count ($ data ); For ($ k = 1; $ k <$ len; $ k ++) { For ($ j = $ len-1, $ I = 0; $ I <$ len-$ k; $ I ++, $ j --) { If (strtoupper ($ sort) = 'desc ') { $ Flag = $ data [$ j] [$ key]> $ data [$ J-1] [$ key]; } Else { $ Flag = $ data [$ j] [$ key] <$ data [$ J-1] [$ key]; } If ($ flag) { $ Tmp = $ data [$ j]; $ Data [$ j] = $ data [$ J-1]; $ Data [$ J-1] = $ tmp; } } } Return $ data; } Usage: $ A = array ( Array ('name' => 'stone ', 'age' => 17, 'sex' => 'male '), Array ('name' => 'sunny ', 'age' => 28 ), Array ('name' => 'grass ', 'age' => 16, 'sex' => 'female '), Array ('name' => 'sea', 'age' => 15, 'birthday' => '2017-08-16 ') ); Print_r (getSortArray ($ a, 'age', 'desc ')); Result: Array ( [0] => Array ( [Name] => sunny [Age] => 28 ) [1] => Array ( [Name] => stone [Age] => 17 [Sex] => male ) [2] => Array ( [Name] => grass [Age] => 16 [Sex] => female ) [3] => Array ( [Name] => sea [Age] => 15 [Birthday] => 1987-08-16 ) )

Do you understand this? Let's look at two examples of array sorting.

To sort the array's age fields, php's simple sort function obviously cannot meet the requirements. Therefore, you need to write a Quick sort code to implement the corresponding requirements.

The Code is as follows:

/** * Description: gets the location of the central point. * * @ Param array $ array * @ Param int $ left * @ Param int $ right * @ Param string $ field * @ Return int */ Function fetcharrayray( & $ array, $ left, $ right, $ field) { // Benchmark Definition $ Stand = $ array [$ left]; // Traverse the Array While ($ left <$ right ){ While ($ left <$ right & $ array [$ right] [$ field] >=$ stand [$ field]) { $ Right --; } If ($ left <$ right ){ $ Array [$ left ++] = $ array [$ right]; } While ($ left <$ right & $ array [$ left] [$ field] <= $ stand [$ field]) { $ Left ++; } If ($ left <$ right ){ $ Array [$ right --] = $ array [$ left]; } } // Obtain the central point $ Array [$ left] = $ stand; Return $ left; } /** * Description: quick sorting of the main program * * @ Param array $ array * @ Param int $ begin * @ Param int $ end * @ Param string $ field */ Function quickSort (& $ array, $ begin, $ end, $ field) { // Variable definition $ Activities = null; If ($ begin <$ end ){ $ Fields = fetcharrayray( $ array, $ begin, $ end, $ field ); QuickSort ($ array, $ begin, $ fields-1, $ field ); QuickSort ($ array, $ struct + 1, $ end, $ field ); } } 2. Call example: $ Array = array ( Array ( 'Name' => "xiao ", 'Age' => 3 ), Array ( 'Name' => 'wang ', 'Age' => 1 ), Array ( 'Name' => 'chen ', 'Age' => 2 ), Array ( 'Name' => 'zhengyi ', 'Age' => 4 ), Array ( 'Name' => 'chai ', 'Age' => 14 ) ); $ Begin = getTime (); QuickSort ($ array, 0, count ($ array)-1, 'age '); Print_r ($ array ); $ End = getTime (); $ Spend = $ end-$ begin; Echo "time spent:". $ spend. "seconds n "; Function getTime () { List ($ msec, $ sec) = explode ("", microtime ()); Return (float) $ msec + (float) $ sec; }