MATLAB provides a simple but efficient sum( ) function to sum column or row vector, as well as all elements in arrays.
Syntax: sum(v,options)
options can be 1 = sum in the row direction (NS) for each column
2 = sum in the column direction (EW) for each row
'all' = sum all elements
if unspecified, sum(v) = sum(v,1)
ILLUSTRATION
