Merge branch 'femwind' of github.com:janmandel/wrf-fire-matlab into femwind
[wrf-fire-matlab.git] / perimeter_new / ros2vec.m
blobc7d6c0d29f87ce9127aa150c0a0fbe312350c179
1 function vec=ros2vec(ros)
2 % from the ros values in 8 directions make vector representation
3 s=1/sqrt(2);
4 r=squeeze(ros)
5 Y=[-s 0 s
6    -1 0 1
7    -s 0 s]
8 X=Y'
9 xx=X.*r
10 yy=Y.*r
11 ii=[3 3 2 1 1 1 2 3];
12 jj=[2 3 3 3 2 1 1 1];    
13 for k=1:8
14     i=ii(k);
15     j=jj(k);
16     plot([xx(i,j)],[yy(i,j)],'*k')
17     rr(k)=r(i,j);
18     hold on
19 end
20 tt=linspace(0,9/4,10)*pi;
21 rr(9:10)=rr(1:2);
22 pp = csape(tt,rr,'periodic');
23 fpolarplot([0,0],@(theta)ppval(pp,theta),500,'-r');
25 % find the vector xs,yz of largest spread
26 % X(i,j)*xs + Y(i,j)*ys = r(i,j)-omni
27 %A = [X(:),Y(:)]; A(5,:)=[];
28 %b = r(:)-omni; b(5)=[];
29 %v= A\b;
30 %f = @(theta)2*omni+v(1)*cos(theta)+v(2)*sin(theta);
32 hold off
33 end
35 function H=fpolarplot(center,f,np,LineSpec)
36 % H=radplot(center,f,np,style)
37 %   center 
38 %   function handle
39 %   np 
40 % adapted from https://www.mathworks.com/matlabcentral/fileexchange/2876-draw-a-circle
41 theta=linspace(0,2*pi,np);
42 rho=f(theta);
43 [x,y]=pol2cart(theta,rho);
44 x=x+center(1);
45 y=y+center(2);
46 H=plot(x,y,LineSpec);
47 axis square;
48 end