Shifting values in a matrix, Alignment of two matrices

I want to align the values of two matrices so that the corresponding values in one column will align the other columns. For example

 A= 
   1 2.5
   2 5.4
   3 4.3
   4 3.3
   5 5.4
   6 2.5

 B=
  6 3.3
  7 5.4
  5 2.5
  3 2.5
  5 5.4
  9 4.3

I want to manipulate matrix B so that it's second column aligns with A so I can get a third matrix

 C =
 1 2.5 3 2.5
 2 5.4 5 5.4
 3 4.3 9 4.3
 4 3.3 6 3.3 
 5 5.4 7 5.4
 6 2.5 5 2.5

Then separate the 1st and 3rd columns

 D=
  1 3 
  2 5
  3 9 
  4 6  
  5 7 
  6 5

Answer 1

[jgg]

I think you can do it this way:

 [~,ind] = ismember(B(:,2),A(:,2))
  C = [A,B(ind)];
  D = C(:,[1,3]);

I'm not sure how well this will perform if they do not perfectly align, though.

[mattyice]

This gives me this for D

D=

     1     3
     2     7
     3     6
     4     6
     5     7
     6     5

Which is incorrect

Answer 2

[Andrei Bobrov]

[~,ib] = sortrows(B,[2 1]);
[~,ia] = sortrows(A,[2 1]);
[~,ia2] = sort(ia);
D = [A(:,1),B(ib(ia2),1)];

Answer 3

[Image Analyst]

Shifting (translating) and sorting are two different things. Which do you want?

For shifting you'd use "register" the array with imregister() or do normalized cross correlation with normxcorr2() (I have a demo if you want it).

For sorting you'd simply use sort() - it's so simple that we hardly need to show you.

[mattyice]

Could I see that demo? I want to basically shift the bottom 3 rows of matrix B to the top of the matrix

[Image Analyst]

Normxcorr2() is used to find a template in another image. The demo is attached.

If you want to shift the image a little bit, it sounds like imregister() is exactly what you want. There are demos for it in the help. I think there are some other functions that are better for very large shifts. Search this forum for imregister or registration or Alex Taylor (the Mathworks developer who wrote them).