1 x=linspace(-5*pi, 5*pi, 500)

     2 plot(x, x, 'b')

     3 plot(x, -x, 'b')

     4 plot(x, sin(x), 'g', linewidth=2)

     5 plot(x, x*sin(x), 'r', linewidth=3)

     6 legend(['x', '-x', 'sin(x)', 'xsin(x)'])

     7 annotate('origin', xy = (0, 0))

     8 title('Four Plot')

     9 xlim(-5*pi, 5*pi)

    10 ylim(-5*pi, 5*pi)

    11 #show()