[jQuery] like 'isset'...determining is something exists on the page

[jQuery] like 'isset'...determining is something exists on the page


I'm trying to determine if soemthing has been set on the page...and
if it is do a different action. I have...
if ($('a#f_' + ide).siblings().is('img'))
{
// do this action
}
else
{
// do something else
}
Which looks to see if an image exists in
I'm expecting that .is() will return true in some cases but it never
does.
Am I going about this entirely the wrong way?
Thanks