mlosch/interp_llc/exch_c.m

function [b] = exch_c(a,o)

[nx ny nt]=size(a);
if nt == 1
elseif nt ~= 6
 nt
 error('Must be tiled array (NxNx6)')
end
if nt == 6 & nx ~= ny
 [nx ny]
 error('Tiles must be square (NxNx6)')
end


if nt == 6
b=NaN*ones(nx+2*o,ny+2*o,6);
b(o+1:o+nx,o+1:o+ny,:)=a;                               % Interior
b(o+1:o+nx,o+ny+(1:o),1)=a(1:o,ny:-1:1,3)';             % N-odd
b(o+1:o+nx,o+ny+(1:o),3)=a(1:o,ny:-1:1,5)';             % N-odd
b(o+1:o+nx,o+ny+(1:o),5)=a(1:o,ny:-1:1,1)';             % N-odd
b(o+1:o+nx,1:o,[1 3 5])=a(:,ny-o+1:ny,[6 2 4]);         % S-odd
b(o+nx+(1:o),o+1:o+ny,[1 3 5])=a(1:o,:,[2 4 6]);        % E-odd
b(1:o,o+1:o+ny,3)=a(nx:-1:1,ny-o+1:ny,1)';              % W-odd
b(1:o,o+1:o+ny,5)=a(nx:-1:1,ny-o+1:ny,3)';              % W-odd
b(1:o,o+1:o+ny,1)=a(nx:-1:1,ny-o+1:ny,5)';              % W-odd
b(o+1:o+nx,o+ny+(1:o),[2 4 6])=a(:,1:o,[3 5 1]);        % N-even
b(o+1:o+nx,1:o,2)=a(nx-o+1:nx,ny:-1:1,6)';              % S-even
b(o+1:o+nx,1:o,4)=a(nx-o+1:nx,ny:-1:1,2)';              % S-even
b(o+1:o+nx,1:o,6)=a(nx-o+1:nx,ny:-1:1,4)';              % S-even
b(o+nx+(1:o),o+1:o+ny,2)=a(nx:-1:1,1:o,4)';             % E-even
b(o+nx+(1:o),o+1:o+ny,4)=a(nx:-1:1,1:o,6)';             % E-even
b(o+nx+(1:o),o+1:o+ny,6)=a(nx:-1:1,1:o,2)';             % E-even
b(1:o,o+1:o+ny,[2 4 6])=a(nx-o+1:nx,:,[1 3 5]);         % W-even
elseif nt == 1
b=NaN*ones(nx+2*o,ny+2*o);
b(o+1:o+nx,o+1:o+ny)=a;                         % Interior
%b(o+1:o+nx,o+ny+(1:o))=a(:,ny:-1:ny-o+1);      % N
%b(o+1:o+nx,1:o)=a(:,o:-1:1);                   % S
b(o+nx+(1:o),:)=b(o+1:o+o,:);                   % E
b(1:o,:)=b(o+nx-o+1:o+nx,:);                    % W
end
1	function [b] = exch_c(a,o)
2
3	[nx ny nt]=size(a);
4	if nt == 1
5	elseif nt ~= 6
6	nt
7	error('Must be tiled array (NxNx6)')
8	end
9	if nt == 6 & nx ~= ny
10	[nx ny]
11	error('Tiles must be square (NxNx6)')
12	end
13
14
15	if nt == 6
16	b=NaNones(nx+2o,ny+2*o,6);
17	b(o+1:o+nx,o+1:o+ny,:)=a; % Interior
18	b(o+1:o+nx,o+ny+(1:o),1)=a(1:o,ny:-1:1,3)'; % N-odd
19	b(o+1:o+nx,o+ny+(1:o),3)=a(1:o,ny:-1:1,5)'; % N-odd
20	b(o+1:o+nx,o+ny+(1:o),5)=a(1:o,ny:-1:1,1)'; % N-odd
21	b(o+1:o+nx,1:o,[1 3 5])=a(:,ny-o+1:ny,[6 2 4]); % S-odd
22	b(o+nx+(1:o),o+1:o+ny,[1 3 5])=a(1:o,:,[2 4 6]); % E-odd
23	b(1:o,o+1:o+ny,3)=a(nx:-1:1,ny-o+1:ny,1)'; % W-odd
24	b(1:o,o+1:o+ny,5)=a(nx:-1:1,ny-o+1:ny,3)'; % W-odd
25	b(1:o,o+1:o+ny,1)=a(nx:-1:1,ny-o+1:ny,5)'; % W-odd
26	b(o+1:o+nx,o+ny+(1:o),[2 4 6])=a(:,1:o,[3 5 1]); % N-even
27	b(o+1:o+nx,1:o,2)=a(nx-o+1:nx,ny:-1:1,6)'; % S-even
28	b(o+1:o+nx,1:o,4)=a(nx-o+1:nx,ny:-1:1,2)'; % S-even
29	b(o+1:o+nx,1:o,6)=a(nx-o+1:nx,ny:-1:1,4)'; % S-even
30	b(o+nx+(1:o),o+1:o+ny,2)=a(nx:-1:1,1:o,4)'; % E-even
31	b(o+nx+(1:o),o+1:o+ny,4)=a(nx:-1:1,1:o,6)'; % E-even
32	b(o+nx+(1:o),o+1:o+ny,6)=a(nx:-1:1,1:o,2)'; % E-even
33	b(1:o,o+1:o+ny,[2 4 6])=a(nx-o+1:nx,:,[1 3 5]); % W-even
34	elseif nt == 1
35	b=NaNones(nx+2o,ny+2*o);
36	b(o+1:o+nx,o+1:o+ny)=a; % Interior
37	%b(o+1:o+nx,o+ny+(1:o))=a(:,ny:-1:ny-o+1); % N
38	%b(o+1:o+nx,1:o)=a(:,o:-1:1); % S
39	b(o+nx+(1:o),:)=b(o+1:o+o,:); % E
40	b(1:o,:)=b(o+nx-o+1:o+nx,:); % W
41	end