Please help me to resolve it . I am using it in Ant Colony algorithm

??? Error using ==> times
Matrix dimensions must agree.

Error in ==> ACO at 215
                p = ((1-rho).*p + rho.*delta_p_current.*v).*delta_p_current +
                p.*(abs(1-delta_p_current));

[monisha silvia]

how did u rectify this error, can u send the code and input image.

Answer 1

[Walter Roberson]

All of the variables you have on that line need to be the same size() or else need to be scalars, but at least one of the variables is not the right size.

[sgb]

thanks for the reply.

I used whos p; whos delta_p_current; it says, Name Size Bytes Class Attributes

p         128x128x3            393216  double              

Name                   Size              Bytes  Class     Attributes

delta_p_current      128x384            393216  double

can you give any correction to resolve it i am new to matlab

[Walter Roberson]

My guess is that at some point you used code similar to

[rows, cols] = size(p);
delta_p_current = zeros(rows, cols);

This is not certain to work, because of an oddity in the definition of the size() function. If you use

s = size(p);

then s would be the vector [128 128 3]

and if you used

[rows cols bands] = size(p)

then rows would be 128, cols would be 128, and bands would be 3.

But if you used

[rows cols] = size(p)

and p has more dimensions than you have variables on the left, then the last variable you gave on the left will be all the remaining dimensions multiplied together -- so in this case, rows would be 128, but cols would be (128 * 3) = 384. In this way, the product of the returned values is always the same as the number of elements in the original array, even though that startles you that the second output is not the size of the second dimension.

[sgb]

Exactly!!!!!!!!!

I changed the input image bit depth to 8 bits and resolved the problem. Thanks a lot for ur timely replies. This is really a good place for learning students. I thank this site very much