I do not understand what you want to do.
One of these should work:
a = [1 2 3]; b = [4 5 6];
for k = 1:min([numel(a) numel(b)])
suma = a(k) + 1;
sumb = b(k) + 1;
end
or:
suma = 0; sumb = 0;
for k = 1:min([numel(a) numel(b)])
suma = a(k) + suma;
sumb = b(k) + sumb;
end
or:
suma = sum(a);
sumb = sum(b);
or maybe something else ...
