Hi, depending on the needs you have you might be interested in my "minimal implementation" of what I call a mock-ndarray. I needed somthing like this to analyze higher dimensional stacks of 2d images and what I needed was mostly the indexing features of nd-arrays. A mockarray is initialized with a list of nd-arrays. The result is a mock array having one additional dimention "in front". >>> a = N.arange(9) >>> b = N.arange(9) >>> a.shape=3,3 >>> b.shape=3,3 >>> c = F.mockNDarray(a,b) >>> c.shape (2, 3, 3) >>> c[2,2,2] >>> c[1,2,2] 8
No memory copy is done. I put the module file here http://drop.io/kpu4bib/asset/mockndarray-py Otherwise this is part of my (BSD) "Priithon" image analysis framework. Regards Sebastian Haase On Wed, Sep 2, 2009 at 11:31 AM, "V. Armando Solé"<s...@esrf.fr> wrote: > Citi, Luca wrote: >> As Gaël pointed out you cannot create A, B and then C >> as the concatenation of A and B without duplicating >> the vectors. >> >> But you can still re-link A to the left elements >> and B to the right ones afterwards by using views into C. >> > > Thanks for the hint. In my case the A array is already present and the > contents of the B array can be read from disk. > > At least I have two workarounds making use of your suggested solution of > re-linking: > > - create the C array, copy the contents of A to it and read the contents > of B directly into C with duplication of the memory of A during some time. > > - save the array A in disk, create the array C, read the contents of A > and B into it and re-link A and B with no duplication but ugly. > > Thanks, > > Armando > > > _______________________________________________ > NumPy-Discussion mailing list > NumPy-Discussion@scipy.org > http://mail.scipy.org/mailman/listinfo/numpy-discussion > _______________________________________________ NumPy-Discussion mailing list NumPy-Discussion@scipy.org http://mail.scipy.org/mailman/listinfo/numpy-discussion
