How can I convert some cell arrays into numbers that can by multiplied by a number?

I have a function that generates a matrix composed of cells (some of them numbers other text). Although this function was initially generated for my GUI, I need to use these values in another function, for that I've used:

setappdata(0,'MatrixData_n',MatrixData_n);
MatrixData_n = getappdata(0,'MatrixData_n')

However now I need to multiply some of the cells of this matrix by a number and I don't know how to convert them in the correct format.

Thanks,

Answer 1

[Image Analyst]

First extract the numerical matrix from the cell that contains a numerical matrix that you want to multiply by some number:

theMatrix = MatrixData_n{index}; % Braces mean "contents of"

where index is the number of the cell from which you want to extract the numerical array. theMatrix is now just the bare numerical matrix - it's not wrapped in a cell. Now multiply the matrix by some number:

scaledMatrix = theMatrix * someNumber;

You can get a good feel for these kinds of operations if you read the FAQ: http://matlab.wikia.com/wiki/FAQ#What_is_a_cell_array.3F

[Leticia Irazola]

Thanks a lot. It's perfectly working.

However I've to add some of the results and as they've different size I've tried to resize them by using

if size(A) > size(B)
 [m,n]=size(A);
 B(m,n)=0;
else
[m,n]=size(B);
 A(m,n)=0;

but it doesn't seem to work. Could you please help me with this? Thanks again

[Walter Roberson]

size() returns a vector, so you are trying to use ">" to compare vectors, which has well defined results but does not mean what you think it does. You need to test the dimensions individually and be prepared for the possibility that one might be higher by the other might be wider so that both of them need to be extended.

[Leticia Irazola]

ok, but how do I know what size should I use to extend both then?

[Guillaume]

One possibility:

[m, n] = max(size(A), size(B))
if any([m n] > size(A))
   A(m, n) = 0;
end
if any([m n] > size(B))
   B(m, n) = 0;
end