Plus42 algebraic expressions update

[Vincent Weber]

Actually wrt to what I was saying about 27S-style list stats, I think we can rule this out. I didn't realize that the 42S can use SIGMA+ with a matrix argument, which means you can store and edit your statistical data in a matrix, which has all the advantages of lists and more (and the GROW option let it grow as wanted). Pages 146-150 and programming examples pages 174-194 of the 42S programming techniques book cover this in great details.

So you could implement ITEM not on lists, but on matrics, in the form ITEM(NAME:i:j) and not just ITEM(NAME:i), and let this be a argument of L(), and you will retain a high level of compatibility with the 27S (just add an argument to ITEM) while using the full power of the 42S

Cheers