On Sat, Mar 15, 2014 at 1:13 PM, Alan G Isaac <alan.is...@gmail.com> wrote: > On 3/15/2014 12:32 AM, Nathaniel Smith wrote: >> I know you were worried >> about losing the .I attribute on matrices if switching to ndarrays for >> teaching -- given that ndarray will probably not get a .I attribute, >> how much would the existence of @@ -1 affect you? > > Not much. Positive integer powers would be useful > (for illustrating e.g. graph theory and difference equations), > but not enough to delay the PEP.
So to be clear, even if numpy.matrix is going away, and even if ndarray isn't getting a .I attribute, then you're just as happy typing/teaching inv(X) as X @@ -1? > I think NumPy should "take the money and run". > Getting `@` is great. Let's get experience with > it before deciding whether it's worth asking for `@@`. > > Questions for `@@`: > - would it just be `matrix_power`, with all the restrictions? > - or would `a(10,2,2)@@-1` return an array of matrix inverses? > - etc The version in the PEP does do gufunc-style broadcasting for >2d arrays, yes. So will np.linalg.matrix_power as soon as someone bothers to send a patch ;-) > In the end, I'd like to see a functional implementation before > deciding on `@@`, but I would not like to see `@` delayed at all. Oh, well, not much is going to affect `@`'s timing, unless we're *dreadfully* slow. Py 3.5 isn't even scheduled yet b/c 3.4 isn't out, and IIUC Python's standard release cycle is 18 months. So we've got a year+ before feature freeze, regardless. -n -- Nathaniel J. Smith Postdoctoral researcher - Informatics - University of Edinburgh http://vorpus.org _______________________________________________ NumPy-Discussion mailing list NumPy-Discussion@scipy.org http://mail.scipy.org/mailman/listinfo/numpy-discussion