MATLAB: Visualizing Dense Areas in cartesian plane

2d griddingpoint density

I have a table that contains x, y coordinates (cartesian)of a large number of points. X coordinates are stored in a column called sp_x and corresponding y coordinates are stored in the column named 'sp_y'.
I download these data to matlab (please see the following coding) and assign x, y values to a matrix called xy. Now I want to see the dense areas (areas where the point density is high). Does anybody know a way to do this? pls help.
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curs1 = exec(conn, 'select sp_x, sp_y from road_part6_trajectories_oneway2_new_segments_cartesian2');
format long;
curs1 = fetch(curs1);
r=rows(curs1);
AA = curs1.Data;
x = [AA{:,1}]';
y = [AA{:,2}]';
for i=1:5
      xy(i,1)=x(i);
      xy(i,2)=y(i);
end;
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Best Answer

xpnts = 100;  %set as desired

ypnts = 100;  %set as desired
minx = min(x);
miny = min(y);
scalex = xpnts ./ (max(x) - minx);
scaley = ypnts ./ (max(y) - miny);
scaledx = 1 + floor(x-minx) * scalex;
scaledy = 1 + floor(y-miny) * scaley;
densemap = accumarray([scaledx(:),scaledy(:)],1);
imagesc(densemap);
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