Ways of performing Accumulation with Dynamic Arrays

tboulden 

Thanks for the links and sample workbook - all sounds like great progress given what is available currently.

I now also have access to Lambda Editor but, as I'm restricted to current channel on corporate licence, it's not much use without LAMBDA! I presume one can make names containing lambdas appear as functions in tooltips and also create function categories for them by opening name manager from a macro sheet (ctrl+f11) or by using the VBE Names properties.

And interesting what you say about empty arrays being a stumbling block. An alternative might be to use an array containing a single blank value which can be returned as an intermediate result eg if blank=SORT(,) then ISBLANK(blank) returns {TRUE}. The INDEX function can preserve blank values like these in results but many other functions can't which makes them tricky to manipulate however.