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Re: Random function

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On 2013-02-25, sonnichjensen@gmail.com <sonnichjensen@gmail.com> wrote:
> I use the rand function to get 10 items of 1808 current itemes.

If you want ten random items from an array, you could try the following:

<?php
// This is the big array you're pulling something out of.
$lotsOfItems = array( /* ... */ );

// This is the empty array that will eventually contain the ten random
// items.
$tenRandomItems = array();

// Generate a range of numbers between 0 and the number of items minus
// one.
$range = range(0, count($lotsOfItems) - 1);

// Shuffle the array of numbers.
shuffle($range);

while (count($tenRandomItems) < 10) {
    $randomOffset = array_shift($range);
    $tenRandomItems []= $lotsOfItems[$randomOffset];
}
?>

Using this code, you will never, ever have a duplicate item. However, it
will be far more computationally expensive than using rand() or
mt_rand().

-- 
Blah blah bleh...
GCS/CM d(-)@>-- s+:- !a C++$ UBL++++$ L+$ W+++$ w M++ Y++ b++

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Random function sonnichjensen@gmail.com - 2013-02-25 12:48 -0800
  Re: Random function Salvatore <sal@yojimbo.hack.invalid> - 2013-02-25 20:57 +0000
    Re: Random function Luuk <luuk@invalid.lan> - 2013-02-25 22:13 +0100
      Re: Random function Jerry Stuckle <jstucklex@attglobal.net> - 2013-02-25 16:42 -0500
      Re: Random function The Natural Philosopher <tnp@invalid.invalid> - 2013-02-25 22:12 +0000
      Re: Random function Robert Heller <heller@deepsoft.com> - 2013-02-25 19:46 -0600
  Re: Random function Jerry Stuckle <jstucklex@attglobal.net> - 2013-02-25 16:39 -0500
  Re: Random function The Natural Philosopher <tnp@invalid.invalid> - 2013-02-25 22:11 +0000
  Re: Random function Salvatore <sal@yojimbo.hack.invalid> - 2013-02-25 22:42 +0000
    Re: Random function "M. Strobel" <sorry_no_mail_here@nowhere.dee> - 2013-02-26 11:18 +0100
      Re: Random function Paul Herber <paul@pherber.com> - 2013-02-26 13:52 +0000
    Re: Random function Markus Grob <snoopy@ilnet.ch> - 2013-02-27 12:17 +0100
      Re: Random function Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-02-28 00:22 +0100

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