MATLAB: Concatenation error while defining a cell variable

Question

I am trying to define a cell variable as

col_req = {'columnA', 'ColumnB',
                'ColumnC'}

and i get the following error. I don't understand why changing line in code causes this error? If cell values are more I can't fit them in one line causing readability issue.

            Dimensions of matrices being concatenated are not consistent.

Answer 1

col_req = {'columnA', 'ColumnB', 'ColumnC' }

OR

col_req = {'columnA', 'ColumnB',........
           'ColumnC' }