I have a 2-d array. e.g.
arr =: 10 6 $ i. 10
I want to get the first 3 columns from the array, e.g. 3{."1and get the first
4 elements, e.g. 4{."1
However, combining these, as in
3 4 {."(0 1) arrgives a length error. Of course 3{. and 4{. will give
different shape results so should be boxed and then concatenated perhaps(?). I
am not sure how to do this, but the end result I want would be something like:
┌─────┐
│0 1 2│
│6 7 8│
│2 3 4│
│8 9 0│
│4 5 6│
│0 1 2│
│6 7 8│
│2 3 4│
│8 9 0│
│4 5 6│
└─────┘
concatenated with
┌───────┐│0 1 2 3││6 7 8 9││2 3 4 5││8 9 0 1││4 5 6 7││0 1 2 3││6 7 8 9││2 3 4
5││8 9 0 1││4 5 6 7│
└───────┘
----------------------------------------------------------------------
For information about J forums see http://www.jsoftware.com/forums.htm
