??? Index exceeds matrix dimensions.

I have the following code (part of a larger program) in `matlab`:

    while(k<n)
    C.(sprintf('Cnew')) = C.(sprintf('C%d',k));
    d1 = equalize_dimension(a.F, C.(sprintf('Cnew')));
    distance_new = distance(d1.x, d1.y);
    k = k + 1;
    end

If you want to substitute values since I have included part of the program, this would be as follows:

    C.(sprintf('Cnew')):

78

And, for `a.F` it is as follows:

78 82 84 80

80 84 86 82

82 87 88 85

82 87 89 86

For the `equalize_dimension(x,y)` function, it is as follows:

    function n = equalize_dimension (x,y)
            [r1 c1] = size(x);
            [r2 c2] = size(y);

            if r1<r2
            e= r2-r1;
            for i=1:e
            x(r1+1,1)=0;
            r1 = r1 + 1;
            end
            [r1 c1] = size(x);
            n.x =x;
            n.y = y;
            end

            if r1>r2
            e = r1-r2;
            for i=1:e
            y(r2+1,1)=0;
            r2 = r2 + 1;
            end
            [r2 c2] = size(y);
            n.x = x;
            n.y = y;
            end

            if c1<c2
            e= c2-c1;
            for i=1:e
            x(1,c1+1)=0;
            c1 = c1 + 1;
            end
            [r1 c1] = size(x);
            n.x = x;
            n.y = y;
            end

            if c1>c2
            e = c1-c2;
            for i=1:e
            y(1,c2+1)=0;
            c2 = c2 + 1;
            end
            [r2 c2] = size(y);
            n.x = x;
            n.y = y;
            end

            if r1==r2 && c1==c2
            n.x =  x;
            n.y = y;
            end

And, for the `distance(x,y)` function, it is as follows:

    function m = distance(x,y)
    [r c] = size(x);
    for i=1:r
         for j=1:c
         summation = (sum(sum(pdist2(x,y))));
         end
    end
         m=summation;
    end

When I run the program, I get the following error:

    ??? Index exceeds matrix dimensions.

    Error in ==> fs at 36
    distance_new = distance(d1.x, d1.y);

Why is that?

Thanks.

Answer 1

[Thorsten]

Probably you have defined a variable distance that shadows the function distance. You can check that by using

 which distance
 distance_new = distance(d1.x, d1.y);

You did not ask for it, but I realized that you can simplify your function equalize_dimension considerably

 function n = equalize_dimension(x, y)
 Z = zeros(max([size(x); size(y)]));
 n.x = Z; n.x(1:size(x, 1), 1:size(x, 2)) = x;
 n.y = Z; n.y(1:size(y, 1), 1:size(y, 2)) = y;

Further I noted that you run your pdist2 function inside the loop always on x and y that do not change depending on i and j.

And please provide the pdist2 function.