OMP_function

0001 function out = OMP_function(y,A,in)
0002 
0003 [M N] = size(A);
0004 Te = M;
0005 if isfield(in,'Te')
0006     Te = in.Te;
0007 end
0008 thresh = 1e-5;
0009 if isfield(in,'thresh')
0010     thresh = in.thresh;
0011 end
0012 
0013 [val_max gamma_omp] = max(abs(A'*y));
0014 
0015 for iter = 1:Te
0016     x_omp = zeros(N,1);
0017     x_omp(gamma_omp) = A(:,gamma_omp)\y;
0018     r_omp = y-A*x_omp;
0019     if norm(r_omp)< thresh
0020         break;
0021     end
0022     p_omp = A'*r_omp;
0023     gamma_ompC = setdiff([1:N],gamma_omp);
0024     [val_omp, ind_omp] = max(abs(p_omp(gamma_ompC)));
0025     gamma_omp = [gamma_omp; gamma_ompC(ind_omp)];
0026 end
0027 out = [];
0028 out.x_out = x_omp;
0029 out.gamma = gamma_omp;
0030 out.iter = iter;