vector input to function

Hi - this is a simple question, more about syntax.

I want to compute a function on a vector.

The function is the procrustes distance function which takes 2 nxm matrices.

procustes( nxm , nxm)

I want to compute it for a ND volume.

For example for a 3D volume

X = rand(2,3,5);

t = 1:5

d = procrustes(X(:,:,t),X(:,:,t));

hoping that d is a 1:5 vector

thanks

Answer 1

[Wayne King]

Then you need to use a for loop and store the results

    X = rand(2,3,5);
    Y = randn(2,3,5);
    for nn = 1:size(X,3)
      d(nn) = procrustes(X(:,:,nn),Y(:,:,nn));
   end

I'm assuming you actually meant to have a different matrix than X as the other input.

[Vesco]

Thank you Wayne. I am currently using a for loop and yes the matrices are different. I was looking for a one-liner tho.

[Jan]

One-liners are more compact and therefore nicer, but not necessarily faster. When they are harder to create and to debug than an loop approach, it is questionable if they are useful.

Answer 2

[Walter Roberson]

d = arrayfun( @(K) procrustes( X(:,:,K), Y(:,:,K) ), 1 : size(X,3) );