condition in a variable - when is it evaluated?

[#1]

Hi,

A document that is supplied to us by a vendor evaluates many chart expressions in something like this manner:

If(Condition1,
   function1($(vVariable1)),
   //(else...)
   function2($(vVariable2))
)

where

vVariable1 = "=if(Condition2,Column1_name,Column2_name)"
vVariable2 = "=if(Condition3,Column3_name,Column4_name)"

What I would like to know is, how many times will Condition2 get evaluated? Once for the whole chart, or once for each row for which Condition1 is true?

Thanks