Contour map from hist3()?

Contour map from hist3()?

Answer 1

[Kelly Kearney]

Supply output variables to hist3:

 [n,c] = hist3(X, [10 10]);
 contour(c{1}, c{2}, n);

[Sandy]

Perfect! Thanks!

[Berks]

Correction - it should be c{2} before c{1}:

contour(c{2}, c{1}, n)

not sure why - just that it works correctly this way, at least in R2013a.

[natprice]

Correction - it should be the transpose of n

contour(c{1}, c{2}, n.');

Example:

set(gcf,'renderer','opengl');

mu = [2 3];
SIGMA = [1 1.5; 1.5 3];
rng default;  % For reproducibility
r = mvnrnd(mu,SIGMA,100);

xb = linspace(min(r(:,1)),max(r(:,1)),20);
yb = linspace(min(r(:,2)),max(r(:,2)),20);
[xx,yy]=meshgrid(xb,yb,20);

[n,c]=hist3(r,{xb yb});

figure()
hold on
plot(r(:,1),r(:,2),'m+')
contour(xx, yy, n.')
hist3(r,{xb yb},'FaceAlpha',.1);
view(3)