P Witte wrote: > Laurence Reeves writes: > > >> P Witte wrote: >> >>> IIRC the resulting sort is "stable" allowing for an unambiguous fast >>> binary >>> search (also included) of the array(s) using the same criteria as for the >>> sort. (That was at least my programming goal. I'll have to check this, >>> though.) >>> >>> >> Sorry? I don't think I follow your banter. A stable sort is one where >> records with equal keys remain in the same order after the sort as they >> were before it. I'm certain that quicksort cannot do that. >> > > You are, of course, right. However the routine can be made to simulate a > stable sort by using an additional array: > > If array$ contains an array to sort and an additional array stabiliser% is > initialised to 0,1,2,..dimn(array$), then > > QUICKSORT array$; 1, stabiliser%; 1 > > produces a stable sort. > > This is, of course, cheating. You have NOT made the sort stable. What you have done is to make the keys unique.
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