Solving for x in y = Tan(x): A Last Resort

[AtlasSniperma]

I know it sounds strange and abstract. and I've only come here as last resort because I couldn't find the answer on google.
If I have y=Tan(x) how do I rearrange that so I have x=?

It's probably a simple answer I've been overlooking, thank you for your time

 

[lurflurf]

http://en.wikipedia.org/wiki/Inverse_trigonometric_functions
http://en.wikipedia.org/wiki/Atan2

x=Arctan(y)
for example if y=1
x=Arctan(1)=pi/4

This function is available on calculators and computers and tables.

 

[AtlasSniperma]

Thank you. Was having difficulty figuring it out.