t = 0 : 0.01 : 3;
c1 = -2 : 2;
c1 = c1(c1 ~= 0);
c2 = c1;
m1 = ones(c2') * c1;
m2 = c2' * ones(c1);
m1 = m1(:);
m2 = m2(:);
x = m1 * exp(-t) + m2 * exp(-2 * t);
plot(t, x);
