Difference between revisions of "LlListSort"

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The sort order is affected by type.<br/>
 
The sort order is affected by type.<br/>
 
Each type is sorted individually and then feathered to have the same order of types.
 
Each type is sorted individually and then feathered to have the same order of types.
<pre>llListSort([1, "C", 3, "A", 2, "B"], 1, TRUE) == [1, "A", 2, "B", 3, "C"]
+
<lsl>llListSort([1, "C", 3, "A", 2, "B"], 1, TRUE) returns [1, "A", 2, "B", 3, "C"]
llListSort([1, 3, 2, "C", "A", "B"], 1, TRUE) == [1, 2, 3, "A", "B", "C"]
+
llListSort([1, 3, 2, "C", "A", "B"], 1, TRUE) returns [1, 2, 3, "A", "B", "C"]
  
llListSort([1, "C", 3, "A", 2, "B"], 2, TRUE) == [1, "C", 2, "B", 3, "A"]</pre>
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llListSort([1, "C", 3, "A", 2, "B"], 2, TRUE) returns [1, "C", 2, "B", 3, "A"]</lsl>
 
|caveats=A bubble sort is a sorting algorithm with a Big O of N*N. Why Linden Labs did not use a N*log(N) sorting algorithm such as [http://en.wikipedia.org/wiki/Heapsort Heap Sort] or [http://en.wikipedia.org/wiki/Mergesort Merge Sort] is unkown...
 
|caveats=A bubble sort is a sorting algorithm with a Big O of N*N. Why Linden Labs did not use a N*log(N) sorting algorithm such as [http://en.wikipedia.org/wiki/Heapsort Heap Sort] or [http://en.wikipedia.org/wiki/Mergesort Merge Sort] is unkown...
 
|constants
 
|constants

Revision as of 16:53, 4 May 2008

Summary

Function: list llListSort( list src, integer stride, integer ascending );

Returns a list that is src sorted by stride.

• list src List to be sorted.
• integer stride number of entries per stride, if less then 1 it is assumed to be 1.
• integer ascending if FALSE then the sort order is descending, otherwise the order is ascending.

Specification

A slow bubble sort is employed to perform the sort.
The sort order is affected by type.
Each type is sorted individually and then feathered to have the same order of types. <lsl>llListSort([1, "C", 3, "A", 2, "B"], 1, TRUE) returns [1, "A", 2, "B", 3, "C"] llListSort([1, 3, 2, "C", "A", "B"], 1, TRUE) returns [1, 2, 3, "A", "B", "C"]

llListSort([1, "C", 3, "A", 2, "B"], 2, TRUE) returns [1, "C", 2, "B", 3, "A"]</lsl>

Caveats

A bubble sort is a sorting algorithm with a Big O of N*N. Why Linden Labs did not use a N*log(N) sorting algorithm such as Heap Sort or Merge Sort is unkown...

All Issues ~ Search JIRA for related Bugs

Examples

<lsl> list numbers = [3, "three", 2, "two", 1, "one"]; default {

   state_entry()
   {
       llOwnerSay(llDumpList2String(numbers, ","));
       // Object: 3,three,2,two,1,one
       numbers = llListSort(numbers, 2, TRUE);
       llOwnerSay(llDumpList2String(numbers, ","));
       // Object: 1,one,2,two,3,three
   }

}

</lsl>

Deep Notes

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Source

lsa_bubble_sort(): 'linden\indra\lscript\lscript_alloc.h'

Signature

function list llListSort( list src, integer stride, integer ascending );