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.
Per
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