How to assign output array to array using indexes

Hey guys,

I have an array called A which has a list of elements in a form of [18 4 5 8 1]. Then I sort A and reach in the following form of [1 4 5 8 18]. Based the sorted array of A, I put it in a function to generate a list of outputs [7 8 9 4 5]. Using the new function outputs, how can I assign the outputs to the original form of A? I know using the built-in functions of "find", but I don't know to use it in a right context. Cheers Ray

Answer 1

[the cyclist]

I am not certain I understand your question. However, I think what you need is the second output argument of the sort command. If you sort A with

[sortedA,sortingIndex] = sort(A)

then the variable sortingIndex gives you the mapping from the unsorted A to sortedA.

Answer 2

[Star Strider]

I believe I understand what you want to do.

Try this:

A = [18 4 5 8 1];
[As,Ix] = sort(A);
Fcn_Output = [7 8 9 4 5];
Result = Fcn_Output(Ix)

Result =
     5     8     9     4     7

The sort function returns an optional second output that are the indices of the sorted argument vector ‘A’. The ‘Result’ vector uses this index vector to rearrange ‘Fcn_Output’ to match the sorted ‘A’.