Henning Thielemann wrote:
I'm uncertain about how who want to put the different kinds of multiplication into one method, even with multi-parameter type classes. You need instances
(*) :: Matrix -> Matrix -> Matrix (*) :: RowVector -> Matrix -> RowVector
[many other instances removed.] Definitely not. You could do: Data Orientation = Row | Column Data Vector a = Vector Orientation [a] (well, the size should be in there too, but I'll skip that). That easily takes care of most of the complexity. And you can easily define operations that can choose to ignore Orientation if they wish (like inner product of vectors). I said that this design works. Of course, implementing it along the lines you suggested in this email would have been idiotic - there is a better way to do it. If you go back to my original email, the sheer complexity of all the combinations possible (several thousand) should have given you a clue that your proposal above was a complete and utter non-starter.
Is the design discussion related to linear algebra for Maple documented somewhere?
Unfortunately not. The design is documented, with some of the discussion captured, but those documents are still in internal papers to Maplesoft Inc. There is no profit to be made in publishing it (in their estimation), so that information remains internal. Jacques