What sort algorithm does PHP use?

Question

Internally speaking, which algorithm(s) does PHP use to implement the various sort functions it offers? It seems like the usort variants might use a different algorithm than the built in sorts, but I wanted to know.

Where would I even find this information?

Thanks!

score 44 · Accepted Answer · edited Sep 05 '11 at 14:20

44

You could find the information by looking at the php manual. http://php.net/sort says PHP uses an implementation of Quicksort. Failing that, you could always trudge through the PHP source code itself.

edited Sep 05 '11 at 14:20

alex

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answered Jul 02 '10 at 13:21

Timothy

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score 21 · Answer 2 · edited Dec 20 '20 at 03:55

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For sorting, PHP uses an implementation of quicksort that can be found in Zend/zend_sort.c, which takes a comparison function and an array of elements. The default comparison function for sort() is defined in ext/standard/array.c and is called php_array_data_compare(). So basically, it's the same algorithm for all sorting functions, except that they take different comparison functions.

edited Dec 20 '20 at 03:55

ggorlen

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answered Jul 02 '10 at 13:35

Daniel Egeberg

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score 0 · Answer 3 · answered Jul 02 '10 at 13:23

0

IIRC, PHP uses quick sort

answered Jul 02 '10 at 13:23

Mark Baker

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Since Timothy "ninja'ed" you in the FGITW game, and because this 5-word answer isn't found to be helpful by any researchers in over a decade, you might entertain the idea of dropping this post from the page. Your call. – mickmackusa Sep 11 '20 at 02:46

What sort algorithm does PHP use?

3 Answers3

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