Forum Discussion
A generalised Lambda helper function that return arrays of arrays using bisection.
I may well be running round in circles but I have learnt a lot from implementing the binary tree. The feature that a really want to hold on to is that the syntax of the final formula (as well as the Lambda function) should match the in-built BYROW precisely. I do have some concerns about computational efficiency though.
I have written a BYCOL version that works will minimal modifications (basically changing ROWS(
I may well be running round in circles
I can only imagine what you brain must feel like in your skull...
I have written a BYCOL version that works will minimal modifications
Can you please share that too?
I would argue that if you successfully covered BYROW and BYCOL, you have covered 70%-80% of the array-of-arrays cases (at least in my limited experience) and made a major contribution to our mental health and welfare.
Is the workbook unstable on your computer? I think I will separate the SCAN, with the thunks used to handle the 2 column array used to collect the Fibonacci series, to another workbook since that is where the trouble started.
I have just submitted 'My Feedback' to Microsoft. It is not a system I am familiar with, so we will see what happens!
Not sure what exactly you mean by "unstable", but I'm having enough occasional hiccups to require me to exit Excel and restart. Very frustrating..
I have completed the alternative approach to the problem of expanding a column of thunks to give a 2D array. As before, the task of generating the column of thunks uses a BYROW wrapper that first reduces the column of row arrays to a column of thunks and then uses a binary tree to expand and stack the results.
I do have concerns relating to the possible efficiency of the process but first one needs to obtain answers and only then does efficiency become relevant!
Sadly, I seem to have messed up the workbook. BYROWλ and BYCOLλ both seemed to be working well but then I started to work on SCANλ and suddenly the workbook started to fall apart. #VALUE! errors show which disappear if one is persistent and re-enter the formula. Only then another formula will suddenly error.
As far as SCANλ is concerned, it was to act as a wrapper for SCAN, but dethunk the accumulation parameter before using it and changing the user-provided Lambda function to apply THUNK to each result. It all seemed so straightforward ...