%-------------------------------------------------------------------------------
% UF Sparse Matrix Collection, Tim Davis
% http://www.cise.ufl.edu/research/sparse/matrices/Luong/photogrammetry
% name: Luong/photogrammetry
% [Photogrammetry problem, B. Luong, FOGALE nanotech, France]
% id: 1895
% date: 2008
% author: B. Luong
% ed: T. Davis
% fields: name title A id date author ed kind b notes
% kind: computer graphics/vision problem
%-------------------------------------------------------------------------------
% notes:
% Photogrammetry problem from Bruno Luong, FOGALE nanotech, France.     
% The problem of interest is:                                           
%     [U S V]=svd(full(A),0);                                           
%     s=diag(S);                                                        
% The spectrum has two parts:                                           
% - the singular values s(1) to s(end-7) are 1.7486e-004 to 3.4655e-007 
% (ratio 504.57).                                                       
% - the singular values s(end-6) to s(end) is smaller than 2.9614e-012  
% (ratio > 5.9e7).                                                      
% So in this problem, the following are considered:                     
% K = span<U(:,end-6:end) > is the kernel of A, and                     
% L = span<U(:,1:end-7) > = orthogonal(K) is isomorph to Im(A).         
%-------------------------------------------------------------------------------
