eeg_topo_murks_contour

 eeg_topo_murks_contour - illustrate isocontours of a surface

0001 function isobars
0002 
0003 % eeg_topo_murks_contour - illustrate isocontours of a surface
0004 
0005 clear; close all;
0006 
0007 s = 40;
0008 w = 1/150;
0009 cvec = 10:60:300;
0010 
0011 p = -s:s;
0012 [x,y] = meshgrid(p);
0013 f = exp(-w*(x.^2 + y.^2));
0014 f = max(f,0);
0015 f = sqrt(f);
0016 
0017 surf(x,y,f); shading interp; hold on; rotate3D
0018 
0019 V = (x + 10).^2 + (y + 10).^2 + f.^2;
0020 
0021 for k = 1:length(cvec)
0022   c = cvec(k);
0023   Vc = (V > c);
0024 
0025 %  Vcdil = dilate(Vc); Vcdil = double(Vcdil);
0026 
0027   se = [0 1 0 ; 1 1 1 ; 0 1 0];
0028 %  se = ones(1);
0029   Vcdil = conv2(Vc,se,'same');
0030   Vcdil = Vcdil > 0;
0031 
0032   Vc = Vcdil - Vc;
0033   Vcvec = find(Vc);
0034 
0035   plot3(x(Vcvec),y(Vcvec),f(Vcvec),'w.')
0036 
0037 end
0038 
0039 hold off