atsettilt

ATSETTILT sets the entrance and exit rotation matrices
 of an element or a group of elements in THERING

 RING=ATSETTILT(RING,ELEMINDEX, PSI)
 ELEMINDEX contains indexes of elements to be rotated
 PSI - angle(s) of rotation in RADIANS
   POSITIVE PSI corresponds to a CORKSCREW (right)
   rotation of the ELEMENT looking in the direction of the beam.
   (or CORKSCREW, aligned with s-axis) rotation of the ELEMENT
   The misalgnment matrixes are stored in fields R1 and R2
   R1 = [  cos(PSI) sin(PSI); -sin(PSI) cos(PSI) ]
   R2 = R1'

 ATSETTILT(ELEMINDEX, PSI) Uses the global variable THERING

 See also ATSETSHIFT

0001 function ring=atsettilt(varargin)
0002 %ATSETTILT sets the entrance and exit rotation matrices
0003 % of an element or a group of elements in THERING
0004 %
0005 % RING=ATSETTILT(RING,ELEMINDEX, PSI)
0006 % ELEMINDEX contains indexes of elements to be rotated
0007 % PSI - angle(s) of rotation in RADIANS
0008 %   POSITIVE PSI corresponds to a CORKSCREW (right)
0009 %   rotation of the ELEMENT looking in the direction of the beam.
0010 %   (or CORKSCREW, aligned with s-axis) rotation of the ELEMENT
0011 %   The misalgnment matrixes are stored in fields R1 and R2
0012 %   R1 = [  cos(PSI) sin(PSI); -sin(PSI) cos(PSI) ]
0013 %   R2 = R1'
0014 %
0015 % ATSETTILT(ELEMINDEX, PSI) Uses the global variable THERING
0016 %
0017 % See also ATSETSHIFT
0018 
0019 global THERING
0020 if ~iscell(varargin{1})
0021     THERING=atsettilt(THERING,varargin{:});
0022 else
0023     [ring,idx,rot]=deal(varargin{:});
0024     
0025     if length(rot) == 1
0026         rot=rot*ones(size(idx));
0027     elseif length(rot) ~= length(idx)
0028         error('AT:length','Vector lengths are incompatible: %i/%i.',length(idx),length(rot))
0029     end
0030     
0031     for i = 1:length(idx)
0032         ring{idx(i)}=attiltelem(ring{idx(i)},rot(i));
0033     end
0034 end