General ⇒ Testing in a document if a package is available

[migf]

Hello,

In a LaTeX document I am preparing I need to know whether a certain package is installed in order either to use it, or use some other alternative without getting an error. I would preferably make some kind of test that would also allow setting a toggle for later use. But I could not find out how to this: is this possible?

Thanks in advance for any help.

[Ijon Tichy]

You can use \IfFileExists to test for the sty-file of the package.

[migf]

Thanks a lot for your reply! This is the kind of stuff I rarely use...