# How to count and plot the number of points in a grid?

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Bhanu Pratap Singh on 17 Feb 2021
Commented: Just Manuel on 2 Mar 2021
I have a huge data set of more than 19,00,000 points. By point I meant x and y. I am creating a 20*20 minor grid in my plot. I would like to count the number of points that fall in a single grid cell and plot/print the number (of points) in the grid itself in an another plot. I tried to look at hist3() and histcounts2() functions but, couldn't get a hold of it.
Please find attached the picture of the figure.
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Bhanu Pratap Singh on 18 Feb 2021
Edited: Bhanu Pratap Singh on 18 Feb 2021
Currently, this is what I am doing. I am not sure, whether I am getting the right output or not. I am using MATLAB R2018a.
%% Read the file into a matrix
C = textscan(fopen('offsets-1.txt'), '%d%d%d%d%f%f%f%f%f%f%f');
% C{6}, C{7} = Easting, northing of Shot Points
% C{8}, C{9} = Easting, northing of Receiver Points
% C{10}, C{11} = Easting, northing of Midpoints Points
sx = C{6}; sy = C{7};
rx = C{6}; ry = C{7};
mx = C{6}; my = C{7};
xedges = min(rx):20:max(rx);
yedges = min(ry):20:max(ry);
nbins_x = length(xedges); nbins_y = length(yedges);
histogram2(mx, my, 'XBinEdges', xedges, 'YBinEdges', yedges, 'DisplayStyle','tile', 'ShowEmptyBins', 'off');
colorbar;
Rik on 18 Feb 2021
Why do you think there might be something wrong? I'm on mobile so I can't run your code, but nothing jumps out at me from your code.

Just Manuel on 17 Feb 2021
Hehe, being curious and doing the stuff mathworks slaps in your face sometimes pays off ;) (I mean the community treasure hunt)
This brought me across this approach to what you want to do:
Have fun watching the Video ;)
Cheers
Manuel
Just Manuel on 2 Mar 2021
Cheers
Manuel