Battery = {

@(x,y) exp(-10*y.^2).*exp(-100*x.^2);

@(x,y) exp(-100*x.^2);

@(x,y) exp(-x.^4/2 - y.^4/2).*(x-y).^2

@(x,y) exp(-x.^2-2*y.^2).*sech(10.*x.*y)

@(x,y) exp(-x.^2-2*y.^2).*(x-y).^2.*sech(10.*x.*y)

@(x) sech(200.*x)

@(x) 2 + cos(100.*x)

@(x) exp(-4.*x.^2).*(9+72.*x.^2 - 192.*x.^4 + 512.*x.^6)

@(x) exp(-x.^2/2).*(1 + (sin(3*x)).^2).*(1 + (cos(5*x).^2))

@(x) exp(-x.^2)

};

domx_array = {

[-1 1]

[-1 1]

[-7 7]

[-5 5]

[-3 3]

[-1 1]

[-1 1]

[-4 4]

[-8 8]

[-10 10]

};

domy_array = {

[-1 1]

[-1 1]

[-7 7]

[-4 4]

[-3 3]

[]

[]

[]

[]

[]

};

for j = 1:length(Battery)

f = Battery{j};

dom1 = domx_array{j};

dom2 = domy_array{j};

if ~isempty(dom2)

[X,Y] = sample(f,dom1,dom2,1000);

g = chebfun2(f,[dom1 dom2]);

contour(g,.01:.1:max2(g)), hold on,

plot(X,Y,'.','markersize',6),

axis([dom1 dom2])

pause(.3)

else

X = sample(f,dom1,100);

g = chebfun(f,dom1);

plot(g), hold on, plot(X,0*X,'.')

xlim([dom1])

pause(1)

end

hold off