Hi, in the context of a problem in the SVAR addon I've stumbled over what might be a bug in msplitby: Consider this: <hansl> clear matrix M = {1,2} matrices MM = msplitby(M, {2}) # gives invalid argument error print MM </hansl> According to the doc, I would have instead expected a result equivalent to: matrices MM = defarray(null, {1,2}) An example with a "taller" matrix works as expected: <hansl> clear matrix M = {1,2; 3,4} matrices MM = msplitby(M, {2,3}) # gives defarray(null, {1,2}, {3,4}), fine print MM </hansl> So it looks to me as if the special case of a 1-element vector (matrix) as the second argument to msplitby() isn't properly handled. Gretl seems to treat it as a scalar then, and as per the documented behavior of msplitby(), the meaning and desired result then changes. In the real-world code that's affected, the length of the second matrix argument can be 1 or more. Of course we can intercept the special case of a single element and work around the problem; but shouldn't msplitby() honor the user's input type also in the special 1-element case? thanks sven