How to display a random item?

[colosimo]

Hello.
I want to upload 4 images to my post and then i want just one image to
be displayed randomly every time you get on the page.

I've got something like that which display everything:

<?php $total = getFieldDuplicates('image', 1);?>
<?php for($i = 1; $i < $total+1; $i++):?>
<?php $imagenum = get('image',1,$i);
echo do_shortcode('[showimage id='.$imagenum .']'); ?>
<?php endfor;?>
<?php } ?>

I'm searching from the missing link, pick just one ranfom $imagenum
and echo just that one.
I'm not a real PHP programmer, but i believe this is pretty easy for
you guys.
Thank you for your help!

c.

[Hunk]

<?php

$num_images = count( getFieldOrder('image') );
$rand_image = rand(5, $num_images);

$imagenum = get('image',1,$rand_image);

echo do_shortcode('[showimage id='.$imagenum .']');

?>

[colosimo]

Thank you very much Hunk!
Does it work even if the number of images is different from 4 or do I
need something different?

c.