Finding the difference between columns in matrix without loops

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I have the results from an iterative process, where the results from each iteration is placed beside eachother, like this:
res =
43.7826 38.8460 38.6889 38.6912 38.6915
107.0735 98.5577 98.1212 98.1170 98.1175
-134.6218 -131.6938 -131.5378 -131.5352 -131.5352
-105.9498 -103.1403 -102.9195 -102.9139 -102.9139
What I want to do is create one matrix that shows the difference between each column, and one matrix that shows the percentage change from one column to the next.
Edit: The first column of the first matrix will be:
diff(:,1) = res(:,2)-res(:,1);
Similar for the second matrix, but there I want the percentage change. This is obviously simple to do using loops, but is there a clever way to do this without loops (maybe using some built-in Matlab functions)?
Thanks.
  2 Comments
per isakson
per isakson on 11 May 2013
... difference between each column ... what exactly does that mean?
John Doe
John Doe on 11 May 2013
The first column of the first matrix will be
diff(:,1) = res(:,2)-res(:,1);
Similar for the second matrix, but in that one I want the percentage change.

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Accepted Answer

Matt J
Matt J on 11 May 2013
firstmatrix=diff(res,1,2);
secondmatrix=100*bsxfun(@rdivide,firstmatrix,res(:,1:end-1));

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