figure(1);
clg
x=linspace(0,pi,50);
y=cos(x);
plot(x,y);
% legend('show')
% legend([2 1.5])
% legend('boxon')
hold on
axis([-1.2 pi+0.2 -1.2 pi+0.2],'equal')
% plot(y,x,';arccos(x);');
plot(y,x);
plot([-1 pi],[0 0],'b',[0 0],[-1 pi],'b');  % show coordinate axis


figure(2);
x=linspace(-2*pi,2*pi,200);
clg;
axis('normal');
axis auto          % leave the scaling up to Matlab
subplot(2,2,1)
plot(x,sin(x));
subplot(2,2,2)
plot(x,cos(x));
subplot(2,2,3)
plot(x,sinh(x));
subplot(2,2,4)
plot(x,cosh(x));
