PYTHON uasort

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Python replacement for PHP's uasort [ edit | history ]
In Python 2.4+, you should sort items by a "key" associated with each element. You provide a function which computes the key for each element.
def uasort(d, keyfunc):
    return sorted(d.items(), key=lambda x: keyfunc(x[1]))


In Python 2.x, you could also use a comparator function, but this feature has been removed in Python 3, and so should no longer be used:
def uasort(d, cmpfunc):
    return sorted(d.items(), key=lambda x: x[1] cmp=cmpfunc)

PHP uasort

PHP original manual for uasort [ show | php.net ]

uasort

(PHP 4, PHP 5)

uasortSort an array with a user-defined comparison function and maintain index association

Description

bool uasort ( array &$array , callback $cmp_function )

This function sorts an array such that array indices maintain their correlation with the array elements they are associated with, using a user-defined comparison function.

This is used mainly when sorting associative arrays where the actual element order is significant.

Parameters

array

The input array.

cmp_function

See usort() and uksort() for examples of user-defined comparison functions.

Return Values

Returns TRUE on success or FALSE on failure.

Examples

Example #1 Basic uasort() example

<?php
// Comparison function
function cmp($a$b) {
    if (
$a == $b) {
        return 
0;
    }
    return (
$a $b) ? -1;
}

// Array to be sorted
$array = array('a' => 4'b' => 8'c' => -1'd' => -9'e' => 2'f' => 5'g' => 3'h' => -4);
print_r($array);

// Sort and print the resulting array
uasort($array'cmp');
print_r($array);
?>

The above example will output:

Array
(
    [a] => 4
    [b] => 8
    [c] => -1
    [d] => -9
    [e] => 2
    [f] => 5
    [g] => 3
    [h] => -4
)
Array
(
    [d] => -9
    [h] => -4
    [c] => -1
    [e] => 2
    [g] => 3
    [a] => 4
    [f] => 5
    [b] => 8
)

See Also

  • usort() - Sort an array by values using a user-defined comparison function
  • uksort() - Sort an array by keys using a user-defined comparison function
  • asort() - Sort an array and maintain index association
  • arsort() - Sort an array in reverse order and maintain index association
  • ksort() - Sort an array by key
  • rsort() - Sort an array in reverse order
  • sort() - Sort an array