matlab_class/gcmfaces_misc/sym_g.m

function [field_out]=sym_g(field_in,sym_in,op_in);

%apply symmetry in the complex plane to field_in(z)
%       where field_in and z are in the complex arrays.
%then, depending on op_in, we apply a compensating operation
%
%format of field_in:
%               z(1,:) is z=-1+?i, z(end,:) is z=1+?i
%               z(:,1) is z=?-i, z(:,end) is z=?+i
%
%sym_in:        1,2,3,4 are reflexions about x=0,y=0,x=y,x=-y
%           4+nRot is rotation by nRot*pi/2
%op_in:         1       apply the opposite complex operation

field_out=field_in;

if sym_in==1;
    field_out=flipdim(field_in,1);
    if op_in==1; field_out=-real(field_out)+i*imag(field_out); end;
elseif sym_in==2;
    field_out=flipdim(field_in,2);
    if op_in==1; field_out=real(field_out)-i*imag(field_out); end;
elseif sym_in==3;
    field_out=field_in.';
    if op_in==1; field_out=imag(field_out)+i*real(field_out); end;
elseif sym_in==4;
    field_out=flipdim(flipdim(field_in,1).',1);
    if op_in==1; field_out=-imag(field_out)-i*real(field_out); end;
elseif sym_in>=5&sym_in<=7;
    for icur=1:sym_in-4;
        field_out=flipdim(field_out.',1);
        if op_in==1; field_out=i*field_out; end;
    end
else;
    fprintf('error in sym_g2\n'); return;
end;

%for test case:
%--------------
%xx=[1:10]'*ones(1,10); yy=xx';
%zz=zeros(10,10); zz(1:2,1:3)=1; zz(8,9)=2; zz(2,6:8)=-1; zz(7,3)=-2;
%sym_g(zz,1); %etc
%with the following uncommented:
%-------------------------------
%figure;
%subplot(2,2,1); imagesc(field_in);
%subplot(2,2,4); imagesc(field_out);
%xlabel('y'); xlabel('x');


1	gforget	1.1	function [field_out]=sym_g(field_in,sym_in,op_in);
2
3			%apply symmetry in the complex plane to field_in(z)
4			% where field_in and z are in the complex arrays.
5			%then, depending on op_in, we apply a compensating operation
6			%
7			%format of field_in:
8			% z(1,:) is z=-1+?i, z(end,:) is z=1+?i
9			% z(:,1) is z=?-i, z(:,end) is z=?+i
10			%
11			%sym_in: 1,2,3,4 are reflexions about x=0,y=0,x=y,x=-y
12			% 4+nRot is rotation by nRot*pi/2
13			%op_in: 1 apply the opposite complex operation
14
15			field_out=field_in;
16
17			if sym_in==1;
18			field_out=flipdim(field_in,1);
19			if op_in==1; field_out=-real(field_out)+i*imag(field_out); end;
20			elseif sym_in==2;
21			field_out=flipdim(field_in,2);
22			if op_in==1; field_out=real(field_out)-i*imag(field_out); end;
23			elseif sym_in==3;
24			field_out=field_in.';
25			if op_in==1; field_out=imag(field_out)+i*real(field_out); end;
26			elseif sym_in==4;
27			field_out=flipdim(flipdim(field_in,1).',1);
28			if op_in==1; field_out=-imag(field_out)-i*real(field_out); end;
29			elseif sym_in>=5&sym_in<=7;
30			for icur=1:sym_in-4;
31			field_out=flipdim(field_out.',1);
32			if op_in==1; field_out=i*field_out; end;
33			end
34			else;
35			fprintf('error in sym_g2\n'); return;
36			end;
37
38			%for test case:
39			%--------------
40			%xx=[1:10]'*ones(1,10); yy=xx';
41			%zz=zeros(10,10); zz(1:2,1:3)=1; zz(8,9)=2; zz(2,6:8)=-1; zz(7,3)=-2;
42			%sym_g(zz,1); %etc
43			%with the following uncommented:
44			%-------------------------------
45			%figure;
46			%subplot(2,2,1); imagesc(field_in);
47			%subplot(2,2,4); imagesc(field_out);
48			%xlabel('y'); xlabel('x');
49
50