Add a zero row or help multiply these matrixes

When you take the difference of a column you are short one row. I would like to add a zero to the beginning of this output. I want to do this because I want to multiply two matrices and I can't do it if they are uneven.

Answer 1

[Image Analyst]

Not exactly sure what you want, but in general:

To prepend a row:

[rows, columns] = size(m);
row0 = zeros(1, columns);
col0 = zeros(rows, 1);
m2 = [row0; m];

To append a row of 0s:

m2 = [m; row0]

To prepend a column of 0s:

m2 = [col0, m];

To append a column of 0s:

m2 = [m, col0];