Re: array_unique broken?
| From: | Melvyn Sopacua | Date: | Tue, 03 Sep 2002 08:20:35 +0000 |
| Subject: | Re: array_unique broken? | ||
| References: | 1 | Groups: | php.dev php.qa |
| Request: | Send a blank email to php-dev+get-87852@lists.php.net to get a copy of this message | ||
On Tue, 3 Sep 2002, Andrey Hristov wrote:
AH>>>
AH>>> Hi,
AH>>> I am not too much in array_unique() but played with array_diff() for a week
AH>>> to implement array_diff_assoc() with no success so far but atm I am dreaming
AH>>> the code of array_diff. I
AH>>> saw that most of the code of array_diff() is in array_intersect() and
AH>>> probably in array_unique() (yup it is like them).
AH>>> The argument is sorted with zend_qsort() by value and nothing is known for
AH>>> the key order in the
AH>>> sorted array.
If (zend_)qsort is the basis for all sorting operations, regarding arrays, isn't
it better then to use a stable sorting routine (I don't know if zend_qsort makes
qsort stable, so if it does, ignore this).
From my personal experience, I expect array_unique, to display more or less the
same functionality as the SQL GROUP construct, leaving the first element of dupli-
cates in tact.
On BSD you have mergesort() but I don't know how portable that is.
--
Melvyn.