How to check if a bundle is already installed?

[Mahammad Nasir]

 
HI,
I have bundle name /bundle symbolic name. and i have a bundle path which i
want to install next. But for some reason i must check if a bundle is
already installed or not. i have around 100 bundles installed.
 
How can i check if a bundle is already installed? i dint find any api to
check if it is already installed. Pls help me
 
 
Regards
Nasir