Hi Chris --
> as with, say, message 9783, how do you know when or when not to use CSE formulae ?
Almost all situations in which 2 or more conditions (as in message 9783) must determine the outcome can be solved with CSE or SUMPRODUCT formulas. Note that there are also other means which can be used such as database functions if they fit.
Some functions require CSE because vector or matrix multiplications are needed for required computations to obtain.
Some situations simply require CSE or kindred functions such as SUMPRODUCT or FREQUENCY because the computations cannot be done with ordinary functions.
> is it just a preference and experience thing,
No, I hope not. The CSE and SUMPRODUCT formulas incur sizeable performance costs when applied to large sets of data. So, they should not be used lightly.
> or is there any black n white logic ?
This is a though question: I believe there are enough clear cut situations nothing else will do.
Bob Umlas and Mark W.,[*] I notice, are online. They may want to comment as well.
[*] in alphabetical order.
Aladin
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