Please see this table, which is – of course – a list of lists.
I have built a function to extract several rows out of a table and return a table which just contains the selected elements of the list/table.
Now its easy to select a single column of a table:
What I am looking for is a function, which returns only selected columns as a table.
I could map 2 columns with a list constructur and would get 2 columns.
But this is limited to 2 elements.
So I don’t know how to create a list constructor with dynamically determined slots
and a variable number of maps according to number of selected columns.
I have built a function which creates result list 1 with a variable number of rows as a selection list. So that works.This is the first step in the function below.
BUT then I have to turn the rows into columns and there I am lacking again a way to dynamically create a list with a variable number of colomns.
So I end up ONLY with 2 columns again, because I dont know how to add a variable number of items to result list 2.
I am just thinking, that there must be any easy way like mapping an element selection of a list/table over some numbers like it works for the rows:
I guess its just my lack of experience with HOF and thinking functional algorithm design.