i need to divide a plot with a grid and color any grid based on the number of point in it

Hello everyone, i need your help.

I have a set of point (x,y) in a matrix nx2.

I need to create a plot that has size L1 and L2 (for example L1=1000 mm and L2=2000 mm) I need to create a grid in the plot with a step of 100 mm, and color every cell with a color based on the number of points that are inside any cell.

if a cell has so many point inside must have a certain color(for ex yellow), if the cell has not so many point must have another color(for ex blue).

thank you in advance

Answer 1

[Michael Madelaire]

Hi

You should be able to use hist3 and imagesc to achieve what you seek:

data = randi(1000, 5000, 2); % Create fake data. 5000x2  with values between 1:1000 (mm)
figure;
resolution = [10, 10]; % This defines the how many bins you want 1000mm/10 = 100mm bin size
[n, q] = hist3(data, resolution);
imagesc(q{:}, n');
xlabel('length [mm]');
ylabel('length [mm]');
c = colorbar;
c.Label.String = 'Amount';

If you want custom colors you have to create you own colorbar. Else try some of the premade.