numbers regex

[Charisma Bypass]

Is there a nice and easy regex I can use to strip the numbers off the *end* of a string?

Eg; 

W1NPPP34

would become W1NPPP

Been hunting google and only come across convoluted methods.  Easy to strip out all the numbers of course, but that doesn't fit the need

Thanks in advance

[JasonD]

Code:

rtrim($foo, '0..9')

Or \d+$ for a regex

[Charisma Bypass]

I never knew rtrim could do that.  Thank you very much Jason.