Hi all, Recently I got to work some more with the matrices module (rref, jordan form for the ODE solver and various coordinate related transformations for the diffgeom module).
The current approach to the issue of Matrix not being a Basic subclass is to use another class called ImmutableMatrix. There is one big drawback in this approach among all its advantages: Interaction between matrices frequently requires rebuilding of the matrix. For instance, imagine a ref method that is used inside the rref method that is used inside the particular_solution method. If they are called on a mutable matrix they must create a copy of this matrix and work on it and then return it. So far so good, however if they are called on an immutable matrix at the end of each method there is an addition rebuild operation, this time transforming the intermediate mutable matrix into an immutable one. Do you think that this is appropriate and worth the cost? Now that we have used both Mutable and ImmutableMatrix for some time, do you think that merging them is possible? Obviously, this again brings up the issue of mutable Basic objects, however this should not be such a big problem if the hashes are calculated properly and if it is well documented. -- You received this message because you are subscribed to the Google Groups "sympy" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
