Bruno Luong

For the moment, it is not recommended using this function for k larger than 1e4, since the insertion complexity is O(k^2), which is not optimal. I'll work for the better insertion algorithm for the next release.

To Matt: this is algorithm designed for for generic polygons (as with INPOLYGON)

About plotting the results:

Jaclyn, if you just want bars plotted for the pairwise densities of two variables (i.e., a plot with x and y axes corresponding to values of your variables, and vertical bars on the x,y grid, corresponding to the counts for each 2D bin), you can get that with hist3().

Will, if you want to plot weights for 3 variables as varying sizes of bubbles on an x,y,z grid, you can do something like this:

% get the histogram
[count edges mid loc] = histcn(vals);

% make a grid for plotting
[X Y Z]=ndgrid(edges{1}, edges{2}, edges{3});
X=X(:); Y=Y(:); Z=Z(:);

% calculate sizes so the most dense cell gets a value of 100
% also convert from volume to "area" (as if drawing a sphere with
% the right volume and cross-sectional area s)
s_scale = 100/(max(count(:))^(2/3));
s = count(:).^(2/3) * s_scale;
% convert any zeros to small numbers for scatter3
s(s==0)=realmin;

% plot the densities
fh=figure();
set(fh, 'Renderer', 'OpenGL'); % faster drawing
scatter3(X, Y, Z, s, 'filled');

I really appreciate it. Great Work!!

Thank you very much, this is working perfectly!

Regards
Xavier