uncondition_Points

% uncondition points, determine conditioning matrix
 see PCV (6.137)

 Usage:
   x = uncondition_Points(xc,M)
  
   xc - Nxd matrix of Cartesian coordinates of conditioned points
   M  - d+1 x d+1 matrix of conditioning

    x  - Nxd matrix of Cartesian coordinates

 Wolfgang Förstner 2/2013
 wfoerstn@uni-bonn.de 

 See also condition_Points, condition_Homography, uncondition_Homography

0001 %% uncondition points, determine conditioning matrix
0002 % see PCV (6.137)
0003 %
0004 % Usage:
0005 %   x = uncondition_Points(xc,M)
0006 %
0007 %   xc - Nxd matrix of Cartesian coordinates of conditioned points
0008 %   M  - d+1 x d+1 matrix of conditioning
0009 %
0010 %    x  - Nxd matrix of Cartesian coordinates
0011 %
0012 % Wolfgang Förstner 2/2013
0013 % wfoerstn@uni-bonn.de
0014 %
0015 % See also condition_Points, condition_Homography, uncondition_Homography
0016 
0017 function x = uncondition_Points(xc,M)
0018 
0019 % number and dimension
0020 [N,d]  =size(xc);
0021 
0022 % condition points
0023 xh =  (inv(M) * [xc ones(N,1)]')';                                          %#ok<MINV>
0024 
0025 % Cartesian coordinates
0026 x = xh(:,1:d);
0027 
0028