Index of reordered vector

Hi all

I better ask my question directly through example

Suppose A = [1 2 3 4 5 6] and I reorder the vector A to get AR = [ 2 4 1 6 5 3]. Now, I wish to track the position of elements of A in AR (i.e. I wish to get vector P = [3 1 6 2 5 4]) so that I can get original vector A by renumbering AR using P (i.e. AO = AR(P) so that A=AO); how can I get vector P?

Regards N Madani SYED

Answer 1

[Matt Kindig]

A = [1 2 3 4 5 6]
AR = [2 4 1 6 5 3]
[junk, P] = ismember(A, AR)

[N Madani SYED]

Thanks.

Answer 2

[Thomas]

A = [1 2 3 4 5 6];
AR=[ 2 4 1 6 5 3];
[x,y,P]=intersect(A,AR)

x =
  Columns 1 through 5
          1.00          2.00          3.00          4.00          5.00
  Column 6
          6.00
y =
  Columns 1 through 5
          1.00          2.00          3.00          4.00          5.00
  Column 6
          6.00
P =
  Columns 1 through 5
          3.00          1.00          6.00          2.00          5.00
  Column 6
          4.00

You have the vector P as output of intersect

[N Madani SYED]

Thanks.