On 23/02/07, Alexander Michael <[EMAIL PROTECTED]> wrote: > I still find the ring buffer solution appealing, but I did not see a > way to stack two arrays together without creating copies. Am I missing > a bit of numpy cleverness?
The short answer is no; the stride in memory from one element to the next must always be the same in an array, and so it's impossible to join two arrays like that without copying. There is a ring-buffer-like idea that lets you do less copying; if you need slices of length N, you can choose M>=2N and maintain a ringbuffer of length M instead; when you push something into the M-N+jth position, you also push (i.e., copy) it into the jth position. Then you can always take a contiguous slice starting anywhere from 0 to M-N-1, and you need only copy a small fraction (N/M or so) of the values pushed on. You never move values in the ringbuffer, and there are no big spikes in CPU time. Anne _______________________________________________ Numpy-discussion mailing list Numpy-discussion@scipy.org http://projects.scipy.org/mailman/listinfo/numpy-discussion
