How can I use the returned sort index from the sort() function on a multidimensional array?

According to the documentation:

[B,I] = sort(___) also returns a collection of index vectors for any of the previous syntaxes. I is the same size as A and describes the arrangement of the elements of A into B along the sorted dimension. For example, if A is a vector, then B = A(I).

However, if A is not a vector, then B ~= A(I) since the sort index is returned as a collection of index vectors oriented along the same dimension that sort operates on rather than a linear index.

Is there a function to convert such a sort index into a linear index array, say f(I), such that B = A(f(I)), where f(x) would be similar in theory to sub2index() with the other dimensions inferred from the size of the sort index?

Answer 1

[Matt J]

The easier way would be to use the attached modification of sort() which will simply return the output indices as lienar indices.

Example:

A=randi(100,5),

A = 5×5

24 33 22 38 11 56 1 48 44 2 90 79 76 97 94 32 18 91 67 73 46 66 72 47 71

[B1,I]=sortlidx(A,2);
B1,

B1 = 5×5

11 22 24 33 38 1 2 44 48 56 76 79 90 94 97 18 32 67 73 91 46 47 66 71 72

B2=A(I)

B2 = 5×5

11 22 24 33 38 1 2 44 48 56 76 79 90 94 97 18 32 67 73 91 46 47 66 71 72