It seems to me that using shapes, (m,1) versus (1,n), to determine whether a vector is column- or row-oriented is a hack (or at least feels like one). If we know we have a vector, then we want to use a single index to obtain a scalar, and that extra "0," or ",0" shouldn't be necessary.
It also seems to me that there is an object-oriented design solution to this, namely defining column_vector and row_vector classes that inherit from matrix, that accept a single index, but behave as matrices consistent with their type. I'm sure there are implications to this I haven't thought through yet, but at least it gives us logical indexing AND persistence of matrices through operations. On Mar 27, 2007, at 1:11 PM, Travis Oliphant wrote: > Thanks for listing your points. I can see that this is an issue > where > reasonable people will disagree because there are multiple ways of > looking at it. > > The idea that matrix selection would return matrices really comes from > wanting to keep matrices more persistent through operations. > > M[0] could be seen either as a 1xn matrix or a n-length array. I > agree that both concepts are possible. Seeing it as a 1xn matrix > allows > matrices to remain persistent more often. > > So, the arguments for the current approach and the arguments > against it > to me seem on the same level, so I don't see a reason to change the > current behavior and see a lot of strong reasons not to change the > behavior (we are in a 1.0 release and could not change anything > until at > least 1.1 anyway). > > With that said: > > One of my goals for the next year or two is to create a matrix > class in > C and incorporate CVXOPT matrices and it's coupled sparse > matrix. We > can re-visit this question in that process. I would like for there to > be a sparse matrix implementation in NumPy (without the solver which > will remain in SciPy). > > But, the sparse matrix and the matrix need to have the same behaviors > and should be able to interoperate with each other. > > So, if you would like to help with that project all input is welcome. ** Bill Spotz ** ** Sandia National Laboratories Voice: (505)845-0170 ** ** P.O. Box 5800 Fax: (505)284-5451 ** ** Albuquerque, NM 87185-0370 Email: [EMAIL PROTECTED] ** _______________________________________________ Numpy-discussion mailing list Numpy-discussion@scipy.org http://projects.scipy.org/mailman/listinfo/numpy-discussion
