% October 2009 
% in this lab we will be trying to make a loop that will display the
% sum of all of the prime numbers in an array
% NOTE: some of the values in the array might be negative!

function[] = Prime(x)
n = length(x(i));
sum = 0;
counter = 0;
for i = 1:n
    j = isprime*(x(i));
        if j=1
            if x(i)>0
                sum = sum + x(i);
                counter = counter + 1;
            end
        end
end
disp('sum')