function plotdata(x, Y)
figure;
hold on;
Pos = find(Y == 1);
Neg = find(Y == 0);
plot(x(Pos, 1), x(Pos, 2), 'k+','LineWidth', 2, ...
'MarkerSize', 7);
plot(x(Neg, 1), x(Neg, 2), 'ko', 'MarkerFaceColor', 'y', ...
'MarkerSize', 7);
hold off;
end