Finally managed to use PyArrayNeighborhoodIter_Next2D with numpy 1.5.0 (in numpy 1.6 it doesn't get along with halffloat). Benchmark results (not the same computer and parameters I used in the previous benchmark): 1. ...Next2D (zero padding, it doesn't accept mirror padding): 10 sec 2. ...Next (zero padding): 53 sec 3. ...Next (mirror padding): 128 sec
Remarks: 1. I did not check the validity of the results 2. Mirror padding is preferable for my specific case. What does it mean for the potential for the neighbourhood iterator acceleration? Nadav. -----Original Message----- From: numpy-discussion-boun...@scipy.org [mailto:numpy-discussion-boun...@scipy.org] On Behalf Of Nadav Horesh Sent: Monday, October 24, 2011 9:02 PM To: Discussion of Numerical Python Subject: Re: [Numpy-discussion] neighborhood iterator speed I found the 2d iterator definition active in numpy 1.6.1. I'll test it. Nadav ________________________________________ From: numpy-discussion-boun...@scipy.org [numpy-discussion-boun...@scipy.org] On Behalf Of David Cournapeau [courn...@gmail.com] Sent: 24 October 2011 16:04 To: Discussion of Numerical Python Subject: Re: [Numpy-discussion] neighborhood iterator speed On Mon, Oct 24, 2011 at 1:23 PM, Nadav Horesh <nad...@visionsense.com> wrote: > * I'll try to implement the 2D iterator as far as far as my programming > expertise goes. It might take few days. I am pretty sure the code is in the history, if you are patient enough to look for it in git history. I can't remember why I removed it (maybe because it was not faster ?). > > * There is a risk in providing a buffer pointer, and for my (and probably > most) use cases it is better for the iterator constructor to provide it. I > was thinking about the possibility to give the iterator a shared memory > pointer, to open a door for multiprocessing. Maybe it is better instead to > provide a contiguous ndarray object to enable a sanity check. One could ask for an optional buffer (if NULL -> auto-allocation). But I would need a more detailed explanation about what you are trying to do to warrant changing the API here. cheers, David _______________________________________________ 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 __________ Information from ESET NOD32 Antivirus, version of virus signature database 4628 (20091122) __________ The message was checked by ESET NOD32 Antivirus. http://www.eset.com _______________________________________________ NumPy-Discussion mailing list NumPy-Discussion@scipy.org http://mail.scipy.org/mailman/listinfo/numpy-discussion
