Extract rows of a matrix containing the same value in the first column by a loop and build a new matrix

Hello,

recently I had a problem with extracting rows of a matrix containing the same value in the first column by a loop.

I got a prompt and good answer:

http://www.mathworks.com/matlabcentral/answers/180108-extract-rows-of-a-matrix-containing-the-same-value-in-the-first-column-by-a-loop

Unfortunately, the above mentioned solution creates a cell as a result and not a matrix.

I already tried to apply A = cell2mat(B) to get the matrix. This command does only work for cells containing arrays with the same length (as far I understood). My arrays in the cell vary in the length of the arrays.

Does anybody know how to have the result as a matrix?

Thank you

Al Falamanki

[Guillaume]

You can't have a matrix where each element is itself a matrix, or worse a bunch of matrices. Such a thing is a cell array. In a matrix, each element is a scalar.

So, why is a cell array a problem for you? and if it really is, give an example of the matrix you expect.