ezcontour() does not plot

I have a distribution with a 1x2 mean vector and a 2x2 covariance matrix. I am trying to display the distribution using ezcontour().

m = [10, 3];
S = [1, 0.7; 0.7, 1];
figure;
G = gmdistribution(m,S);
F = @(x,y) pdf(G,[x y]);
ezcontour(F,[-10,20]);

However, the plot I get is something like this:

Why is this happening? Can you please help me?

Answer 1

[Walter Roberson]

fcontour(F, [-10, 20]) works, if you have R2016a or later