How exactly are you looping? That sounds absurdly slow. What you need is a fast dictionary.
On Wed, Aug 4, 2010 at 6:00 PM, Gökhan Sever <[email protected]> wrote: > > > On Wed, Aug 4, 2010 at 6:59 PM, <[email protected]> wrote: > >> Hey folks, >> >> I've one array, x, that you could define as follows: >> [[1, 2.25], >> [2, 2.50], >> [3, 2.25], >> [4, 0.00], >> [8, 0.00], >> [9, 2.75]] >> >> Then my second array, y, is: >> [[1, 0.00], >> [2, 0.00], >> [3, 0.00], >> [4, 0.00], >> [5, 0.00], >> [6, 0.00], >> [7, 0.00], >> [8, 0.00], >> [9, 0.00], >> [10,0.00]] >> >> Is there a concise, Numpythonic way to copy the values of x[:,1] over to >> y[:,1] where x[:,0] = y[:,0]? Resulting in, z: >> [[1, 2.25], >> [2, 2.50], >> [3, 2.25], >> [4, 0.00], >> [5, 0.00], >> [6, 0.00], >> [7, 0.00], >> [8, 0.00], >> [9, 2.75], >> [10,0.00]] >> >> My current task has len(x) = 25000 and len(y) = 350000 and looping through >> is quite slow unfortunately. >> >> Many thanks, >> -paul >> >> >> _______________________________________________ >> NumPy-Discussion mailing list >> [email protected] >> http://mail.scipy.org/mailman/listinfo/numpy-discussion >> > > My simplest approach would be: > > y[x[:0]-1] = x > > # Providing the arrays are nicely ordered and 1st column x is all integer. > > -- > Gökhan > > _______________________________________________ > NumPy-Discussion mailing list > [email protected] > http://mail.scipy.org/mailman/listinfo/numpy-discussion > >
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