Bug #2322

There's an error in function median() in current _stable_ release

Details

Submitted	2004-09-13 17:35 UTC
From	tomasz dot frelik at enzo dot pl
Status	Bogus
Package	Math_Stats
PHP Version	Irrelevant
OS	Irrelevant
Roadmaps	(Not assigned)

Comments

[2004-09-13 17:35 UTC] tomasz dot frelik at enzo dot pl

Description:
------------
Original code in median():

$n = count($arr);
$h = intval($n / 2);
if ($n % 2 == 0) {
$median = ($arr[$h] + $arr[$h - 1]) / 2;
} else {
$median = $arr[$h + 1]; // <--- HERE
}

I believe the line should read

$median = $arr[$h];

For example, n=5, h=intval(2.5), h=2
We are interested in the 3rd element of an array, it's index is 2.

[2004-09-14 11:56 UTC] tomasz dot frelik at enzo dot pl

There are two versions of the package in Current Release section. I downloaded the one labeled "stable", because I'd assume that's the right choice when looking for production-quality code. The bug is fixed in "beta", but still present in "stable" release.