Sorry if this is the wrong spot for this, but i'm currently writing code in Microsoft Visual Basic in excel 2000.

here is the beginning of a function

Function ErlBLines(blockingProbablity as Double, traffic as Double) as Double
...
...
End Function


One thing i could do with Python is give a variable a value that was optional. Basically it would remain the same value unless the user changed it.


so in python what i wan to do would look like this


def ErlBLines(blockingProbability, traffic, error=0):
...
...
return ...

Is there a way i can do this in VB?

Basically i want ether of these to be acceptable inputs in excel.

=ErlBLines(.02,10)

And

=ErlBLines(.02,10,.1)


Thanks for your help in advance