From: Steph T on
Thank you both for your help, but this is actually an accidental double posting, and the problem was solved in the other (main) post.

I don't have any NaNs 'inside' the matrix, just at the start and finish;

NaN NaN etc...
2 56 etc..
3 70
8 90
4 81
9 17
1 10
NaN NaN
NaN NaN

Thus I just looped through each column :) not elegant, but it works well

Thanks though,
Steph