cycling/detection_ellipse.m

   1 function e = detection_ellipse(g,r)
   2 %function e = detection_ellipse(g)
   3 % function returns eigenvectors for ellipse containg fire detections
   4 % inputs;
   5 %   g        struct, detection structure from subset_detections
   6 %   r       struct, fire data from subset_domain
   7 %output:
   8 %   e        struct with eigenvectors for ellipse contining detections
   9
  10 d = detection_list(g,r);
  11 fire_idx = find(d);
  12 fires = zeros(length(fire_idx),2);
  13 fire_lons = r.fxlong(fire_idx);
  14 fire_lats = r.fxlat(fire_idx);
  15 fires(:,1) = fire_lons;
  16 fires(:,2) = fire_lats;
  17
  18 %[sat_in,sat_on] = inpolygon(r.fxlong(:),r.fxlat(:),fire_lons,fire_lats);
  19 fire_area = length(fire_idx);
  20 %fprintf('satellite area ~= %d \n',fire_area);
  21
  22 %scatter plot the detections
  23 % figure,scatter(fire_lons,fire_lats)
  24 % hold on
  25 % shrink = 0.75;
  26 % k = boundary(fire_lons,fire_lats,shrink);
  27 % plot(fire_lons(k),fire_lats(k));
  28
  29 e = ellipse_fit(fires,1.96);
  30 e.area = fire_area;
  31 e.ellipse_area = det(e.d);
  32
  33
  34
  35 end