Stuart Brorson wrote: > On Fri, 4 Jan 2008, Stuart Brorson wrote: > >>> I just discovered this today. It looks like a bug to me. Please >>> flame me mercilessly if I am wrong! :-) > > FWIW, here's what Matlab does: > >>> A = rand(1, 4) + rand(1, 4)*i > > A = > > Columns 1 through 3 > > 0.7833 + 0.7942i 0.6808 + 0.0592i 0.4611 + 0.6029i > > Column 4 > > 0.5678 + 0.0503i > >>> B = zeros(1, 4) > > B = > > 0 0 0 0 > >>> for idx=1:4; B(idx) = A(idx); end >>> B > > B = > > Columns 1 through 3 > > 0.7833 + 0.7942i 0.6808 + 0.0592i 0.4611 + 0.6029i > > Column 4 > > 0.5678 + 0.0503i > > > I realize NumPy != Matlab, but I'd wager that most users would think > that this is the natural behavior......
Well, that behavior won't happen. We won't mutate the dtype of the array because of assignment. Matlab has copy(-on-write) semantics for things like slices while we have view semantics. We can't safely do the reallocation of memory [1]. [1] Well, we do have a .resize() method which will do the reallocation and raise an exception if there are views lingering about. However, this is only done when explicitly asked for because this is a feature that is useful in a limited number of situations. We will not allow it to be done implicitly. -- Robert Kern "I have come to believe that the whole world is an enigma, a harmless enigma that is made terrible by our own mad attempt to interpret it as though it had an underlying truth." -- Umberto Eco _______________________________________________ Numpy-discussion mailing list Numpy-discussion@scipy.org http://projects.scipy.org/mailman/listinfo/numpy-discussion
