 f1 = @(x) (x^2)
 f  = @(x) (x.^2)

 g1 = @(x,y) (x^2 + y^2)^2 - (x^2 -y^2)
 g  = @(x,y) (x.^2 + y.^2).^2 - (x.^2 -y.^2)

 hold off
 fplot(f1,[-5 5 -5 5 ])
 w=input('press any key to continue');
 fplot(f,[-5 5 -5 5 ])

 ezplot(g1)
 w=input('press any key to continue');
 fprintf('If you have encountered a warning ignore it\n')
 ezplot(g,[-2 2 -2 2])

 w=input('press any key to continue');
 x= 10*rand(100,1);
 hist(x)
 w=input('press any key to continue');
 hist(x,5)
 w=input('press any key to continue');

 [a b] =hist(x,5,'r');
 h = findobj(gca,'Type','patch');
 set(h(1),'Facecolor','r','EdgeColor','m');
 w=input('press any key to continue');
 set(h(1),'Facecolor','g','EdgeColor','y');

 w=input('press any key to continue');

 bar(b,a,'r');grid;hold on
