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Sorting question.  RSS feed

 
Greenhorn
Posts: 26
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Hello all,

There is a simple way to sort in java using Arrays.sort. However, is there anyway i can get an array of indexes which tells me whats the old position of that sorted element? For people who have used Matlab ( [sortval sortpos] = sort(z,'ascend') ), its the sortpos matrix.

for example:-
z = [ 1 10 2 5 4 ]
When you sort you get:-
z_sorted = [ 1 2 4 5 10 ]
I also need an array like this:-
indexs = [ 1 3 5 4 2 ]

I know i can do some post processing on the sorted array to get this, however i was wondering if there is some inbuilt way in java (or some really quick way) of doing this.

Thanks in advance'
Neville
 
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This exact same question has come up last week or so: http://www.coderanch.com/t/451158/Java-General-beginner/java/Helping-Sorting-Array-Doubles-But
 
It is sorta covered in the JavaRanch Style Guide.
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