MATLAB: Removing boxes with a low amount of data points

boxdatafindinterpolationMapping Toolboxpointsremovetriscatteredinterp

Hello,

I have scattered data points on a 3127 x 254 grid. I would like to interpolate this onto a regular grid (which I have done with triscatteredInterp) but now I would like to find and remove grid boxes that contained less than 30 data points when interpolation took place.

Does anyone know how I could do this?

thanks, Michael

Best Answer

Since I can't try your code, all I can suggest is to do a convolution on your array, if you can get your array that is basically a "map" with counts as the values:

window = ones(7);  % Look everywhere in a sliding 7 by 7 window
% Count in each window
sumInWindows = conv(theCountArray, window, 'same');
% Find where count is below, say, 30
binaryImage = sumInWindows  < 30;
image(binaryImage);

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