How much can I milk out of the rand(); function?

obyno

Hi, I was wondering if there is a function in php lets me generate x numbers randomly from a giving range.
For instance is there a way I can, presented with minimum=1 and maximum=20 generate three random numbers x,y,z in one pass of the rand(min, max); function.
Thanks everyone.

Sxooter

Not really. but it's easy to loop over:

$max = 3;
for ($i=0;$i<$max;$i++){
  $r[]=rand(1,20);
}
print implode(":",$r);

obyno

Thanks very much.The solution works except that it actually yields x random numbers from within three rand(); sessions.Like so:

$max = 3;
for ($i=0;$i<$max;$i++){
$r[]=rand(1,20);
}
$q=implode("&nbsp", $r);
echo $q;

echo " ";
echo $r["0"];
echo " ";

echo " ";
echo $r["1"];
echo " ";

echo " ";
echo $r["2"];
echo " ";

if you keep refreshing the page the same number comes up twice or even more in each fresh page.

what I would appreciate is a way to make x random numbers from the same rand(); session so that at every time the x random numbers are always different.x

superwormy

If the numbers HAVE to be different... then its not really randomly generating them now is it?

In that case, I would just check after each random number generated that it doesnt match one of the others.

Put it in a while () loop, while ( number of unique random numbers foudn is less than 4... )

Note that you should seed the random number generator in older versions of PHP also...

Sxooter

Originally posted by superwormy

Note that you should seed the random number generator in older versions of PHP also...

Actually, you should always seed it, you just never know how non-random the machine your code is gonna run on is.

Is that a sentence?

Anyway, the seeding part is right there on rand(), so I kinda didn't bother mentioning it.

What obyno was asking for actually was a shuffling algorhythm.

Here, we create a list of all possible values and then shuffle the array.

anyway, this is all covered in the manual under the shuffle command, so I'll just post the link, as the example code is almost exactly what obyno wants already.

http://css120.ihs.com/php/function.shuffle.html

Weedpacket

Ah, so you want a random sample.

[man]array_rand[/man] will do that. To get the array of values you want to use, you could use [man]range[/man].