Random Values

BenRussell · Jul 15, 2001

Say I have an array like the following :
@Values = ("3", "8", "2", "0", "23" , "5&quot

;
And I wanted to randomly select one of the numbers in there (These will not always be the numbers, but I am making an ad rotator program and these will refer to account numbers that contain banner information, etc.) How would I select one of the numbers and assign it to $SelectedValue?
Someone said to use
$SelectedValue = $Values[floor rand @Values];
But this gives an internal server error. I took out the floor, and it does not generate a random number, it picks the same number every time. - Ben Russell
- President of Intracor Technologies (

http://intracor.hypermart.net)

Rieekan · Jul 16, 2001

Try this. I'm sure it's not the cleanest way to do it, but it seems to work.

$array = @Values #To get the length of the array
$SelectedValue = int( rand($array)) #To generate the random number

- George

tsdragon · Jul 16, 2001

You can also use:

Code:

$SelectedValue = $Values[rand $#Values+1];

Using the scalar value of @Values like the above posting won't work very well because it will only return 0 if the array is empty (it's the NUMBER of elements in the array, not the subscript of the last value). $#Values will give you the subscript of the last value. rand will give you a fractional random number between 0 and the subscript of the last value of the array. Perl will automatically drop any fractional part in a subscript, so you don't need to worry about that, but in order to get it to use the last element, you've got to go one higher on the limit.
Tracy Dryden
tracy@bydisn.com

Meddle not in the affairs of dragons,
For you are crunchy, and good with mustard.

BenRussell · Jul 16, 2001

That still doesn't work. I use the following code to display the ads :

@Values = ("1", "2&quot

;

$SelectedValue = $Values[rand $#Values+1];

if ($SelectedValue = "1&quot

{
print "Content-type: text/html\n\n";
print <<"EOF";

<HTML>
<HEAD><TITLE>Ad Server</TITLE></HEAD>
<BODY BGCOLOR="#FFFFFF">

<A HREF="

http://www.legacy-network.com"

TARGET="_top"><IMG SRC="

http://adserver.legacy-network.com/Ads/TLNBanner.gif"

WIDTH="468" HEIGHT="60" BORDER="0"></A>

EOF
} elsif ($SelectedValue = "2&quot

{
print "Content-type: text/html\n\n";
print <<"EOF";

<HTML>
<HEAD><TITLE>Ad Server</TITLE></HEAD>
<BODY BGCOLOR="#FFFFFF">

<a href="

http://www.fineclicks.com/php-bin/click.php3?h=tln&pid=31&bid=109&t=ban1"

target=_top><img src="

http://www.fineclicks.com/php-bin/image.php3?h=tln&pid=31&bid=109&t=ban1"

width=468 height=60 border=0 alt="Please click here to visit our sponsor"></a>

EOF
}

--- End of code ---
But it only displays the first ad every time.
You can go to

http://adserver.legacy-network.com/Ads.cgi

to see. - Ben Russell
- President of Intracor Technologies (

http://intracor.hypermart.net)

Rieekan · Jul 17, 2001

You need to change the if and elsif statements to state:

(els)if ($SelectedValue eq "#&quot

Where # is the value of the element in the array.

Your current code is always reassigning $SelectedValue to 1 when it hits the first if statement, causing your first ad to always display.

I did run your code with these changes through my webserver and they did work, showing both ads randomly.

Hope this helps!

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Random Values

BenRussell

Programmer

Rieekan

Programmer

tsdragon

Programmer

BenRussell

Programmer

Rieekan

Programmer

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