How to sort an array in descending order and you also have idea about the position to which it descend ?

I have an array of any length and I want to sort them in descending order. The position and value in that matrix refer to an ID of a node. So my question is that how I can sort this array in descending order and I should have idea of node position in array after sorting out.

Like I have a matrix A and the first value of the array is 5 but its ID is 1 and second value is 4 and its ID is 2 so after descending it goes to some new position 11 and 4 to 12 in the array. then whether i can get in a variable the position of variables after sorting out.

if true
  A = [ 5 4 61 7 1 3 35 67 11 44 83 48 110 6]
  B = sort (A, 'descend');
  B =  110    83    67    61    48    44    35    11     7     6     5     4     3     1
  ID_pos of 5 = 11 and ID_pos of 4 = 12 so how to get these index automatically. 
end

Kindly guide me

Answer 1

[Star Strider]

Use the ismember function:

A = [ 5 4 61 7 1 3 35 67 11 44 83 48 110 6];
B = sort (A, 'descend');

[~,Idx] = ismember([5 4], B)

Idx =
    11    12

[Arsal15]

Star Strider

I am really thankful for your simple and unique solution. I need one hint in another question I posted, if you can.

[Star Strider]

My pleasure.

I didn’t see your other Question listed on your Profile page just now, so I’ll look for it.

Answer 2

[Roger Stafford]

You can use the second argument produced by 'sort':

   [B,p] = sort(A,'descend');
   q = 1:length(p);
   q(p) = q;

The values in 'q' will give the indices with respect to 'B' of the corresponding positions in 'A'.

[Arsal15]

But this solution makes the matlab to get crash ?

I don't know why ?

[Roger Stafford]

I don't know why either. On my computer I get the result

q =
  11 12 4 9 14 13 7 3 8 6 2 5 1 10

which I believe is the solution you wished to obtain.