Since the running time of the maximum_n_ind() is O(N*M) and the running time of the quicksort algorithm averages as O(N*ln(N)) with a worst case of O(N**2) you'll do better with qsort first when ln(N) is about M in size which is 17 for N = 5000**2. That means that for small M doing the qsort second is best but for large N doing qsort as Derek suggested will be faster.
If you really need to optimize your performance, you need to time the various approaches to see which is faster and when. Hope this helps, Chris On Mon, Oct 20, 2014 at 9:50 AM, Chris Marshall <[email protected]> wrote: > qsort is using quicksort so the performance is that of > quicksort. It would probably be faster to use maximum_n_ind > with an appropriately large number for N and then use qsort > or uniq to determine which elements you need. > > --Chris > > On Mon, Oct 20, 2014 at 4:17 AM, Ronak Agrawal <[email protected]> wrote: >> >> Thanks Chris and Derek for the optimized method >> >> For unique I was going to use squaretotri() and then sort it >> The rle had went out of my mind... >> >> I have a doubt, is it efficient to use the qsort method in large matrix ( >> say 5000 x 5000) _______________________________________________ Perldl mailing list [email protected] http://mailman.jach.hawaii.edu/mailman/listinfo/perldl
