Pierre GM wrote: > On Wednesday 20 December 2006 18:02, Tom Denniston wrote: >> If you want the n largest item i would recommend quicksort > ... >> I don't know of a way to do this in numpy. I think it would require >> adding a cfunction to numpy. Perhaps an "argnth" function? >> >> Does anyone else know of an existing mechanism? > > Is it really needed when you have argsort ? >>>> x=N.array([1,3,5,2,4]) >>>> ax=N.argsort(x) >>>> ax > array([0, 3, 1, 4, 2]) >>>> x[ax[0]], x[ax[-1]], x[ax-3]] > 1, 5, 3 > > Or am I once again missing the point entirely ?
There are algorithms that can be faster if you can ignore the bulk of the irrelevant data. -- 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 [email protected] http://projects.scipy.org/mailman/listinfo/numpy-discussion
