I need a VI that will very quickly (n log n) sort a 1D array of doubles. This VI should not only output the sorted array, but for each of the sorted array elements, it should also output that sorted array element's position in the unsorted array. So for example if the input array were: unsorted_array 4.1 2.3 7.0 5.6 10.2 Then the output arrays would be: sorted_array 2.3 4.1 5.6 7.0 10.2 indices_array 1 (the value 2.3 is located at position 1 in the unsorted_array) 0 (the value 4.1 is located at position 0 in the unsorted_array) 3 (the value 5.6 is located at position 3 in the unsorted_array) 2 (the value 7.0 is located at position 2 in the unsorted_array) 4 (the value 10.2 is located at position 4 in the unsorted_array) This way I could generate the sorted_array using just the indices_array and the unsorted_array. Has anyone written a nifty piece of code to do this? I did some research on (n log n) sorting algorithms but most of them use recursion which I don't know how to do in LabVIEW. It would also be nice to have an algorithm like this that could sort an array of strings. cheers, Richard

LabVIEW

I need sorting VI that returns the sorted array element's positions in the unsorted array

Shane,

Was the hyper threaded code done in LV 7.0 or earlier? If so that might have been the problem with performance since LV7.1.1 has been optimized for hyperthreading, see: http://zone.ni.com/devzone/conceptd.nsf/webmain/01F2E634710FB8E486256E2900586D41

This article shows a 2x decrease in performance in a hyperthreaded code under LV7.0 while the same code had a 2x increase in performance, an almost 4x total difference. I have not looked into this too much yet but am getting the signals from Intel and competitors that multiprocessors are the committed future of the desktop PC and no longer just for supercomputers.

Paul

Paul Falkenstein
Coleman Technologies Inc.
CLA, CPI, AIA-Vision
Labview 4.0- 2013, RT, Vision, FPGA

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LabVIEW

I need sorting VI that returns the sorted array element's positions in the unsorted array

Re: I need sorting VI that returns the sorted array element's positions in the unsorted array