Forum Discussion
How to sum an array, after applying a few conditions to it? It's complicated, I'm attaching a file.
Very often intermediate results are re-used multiple times. So a single formula tends to get bigger and takes more calculation time.
I know there is now LET() but I am not getting warm with it - yet.
If you really want to build a single formula you have to build helper columns first and then try to put them together.
Agreed. I probably glossed over "despite that, there are reasons of computational efficiency that might justify creating an array of intermediate results" too hastily.
That said, one of the benefits of the LET function is that the local names are not re-evaluated upon each use, so the computational efficiency is achieved without repainting the screen with intermediate results.
Yes, I did use helper ranges (scratch space) while I was developing parts of the formula. The final steps were the 'packaging' of the solution, but the process does not create the nested formula nightmares that results from developing traditional formulas without helper ranges.