scatstat2documentation
Thescatstat2function returns statistical values of all points within a given radius of each value. This is similar to taking a moving mean, but points do not need to be equally spaced.
See alsoscatstat1.
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Syntax
zbar = scatstat2(x,y,z,radius) zbar = scatstat2(x,y,z,radius,fun) ybar = scatstat1(...,options)
描述
zbar = scatstat2(x,y,z,radius)returns the mean of allzvalues within specified radius at each point (x,y).
zbar = scatstat2(x,y,z,radius,fun)applies any function fun tozvalues, defaultfunis@mean, but it could be anything you want, even your own anonymous function.
zbar = scatstat2(...,options)allows any options that the function accepts. For example, 'omitnan'.
Example: Local median
Consider this noisy data set of 5000 scattered points:
N = 5000; x = randi(750,N,1); y = randi(750,N,1);% z contains *real* structure, plus lots of noise:z = sind(x) + cosd(y) + 3*randn(size(x)); scatter(x,y,10,z,'filled') axisimagetitle'noisy scattered 2D data'
It almost looks like there's nothing there but noise. Filter out the high-frequency noise by taking the local median within a 75 unit radius:
z_median = scatstat2(x,y,z,75,@median); scatter(x,y,10,z_median,'filled') axisimagetitle'local median'
Author info:
This function was written byChad A. Greeneof the University of Texas at Austin's Institute for Geophysics (UTIG), June 2016.