Visibility of a var outside a cycle

[DrD]

Yes, (1024,1204), I was going to mention that, as an interesting 'twist' on the inner digits, but I thought it too obvious to mention. From your code fragment, I couldn't determine what you were actually working with, so I just made up a dummy list (DL) that equates to the coded example, returning your expected result. Within that there may be a useful hint(s) you might find useful to actually accomplish your own objectives.

Over the years, I've grown fond of using lists. In general they are much faster more efficient, and powerful, (for me), to understand than matrices, and I find them to be way easier to work with, even though I have recently completed a couple of courses in linear algebra. While fun to do at the time, trying to remember all the various rules and tools of matrices is a true case of diminishing returns, in my case!

-Dale-