Tidying up a list
- by Jonas
I'm fairly sure there should be an elegant solution to this (in Matlab), but I just can't think of it right now.
I have a list with [classIndex, start, end], and I want to collapse consecutive class indices into one group like so:
This
1 1 40
2 46 53
2 55 55
2 57 64
2 67 67
3 68 91
1 94 107
Should turn into this
1 1 40
2 46 67
3 68 91
1 94 107
How do I do that?
EDIT
Never mind, I think I got it - it's almost like fmarc's solution, but gets the indices right
a=[ 1 1 40
2 46 53
2 55 55
2 57 64
2 67 67
3 68 91
1 94 107];
d = diff(a(:,1));
startIdx = logical([1;d]);
endIdx = logical([d;1]);
b = [a(startIdx,1),a(startIdx,2),a(endIdx,3)];
