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more elaborate example with non-stat. estimate explanation
author smusevic
date Tue, 30 Jul 2013 09:56:27 +0100
parents a4a7e3405062
children
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% solve multiple 3rd degree linear systems at once - no pivoting!
function dg3 = lin_solve_dgr_3(A,b,R)
  nrm =  ...
    + A(1,3,:) .* A(2,2,:) .* A(3,1,:) ...
    - A(1,3,:) .* A(2,1,:) .* A(3,2,:) ...
    + A(1,2,:) .* A(2,1,:) .* A(3,3,:) ...
    - A(1,2,:) .* A(2,3,:) .* A(3,1,:) ...
    + A(1,1,:) .* A(2,3,:) .* A(3,2,:) ...
    - A(1,1,:) .* A(2,2,:) .* A(3,3,:);
  dg3 = zeros(3,R);
  dg3(1,:) = -(...
    +b(3,1,:) .* ( A(1,2,:) .* A(2,3,:) - A(1,3,:) .* A(2,2,:) ) ...
    -b(2,1,:) .* ( A(1,2,:) .* A(3,3,:) - A(1,3,:) .* A(3,2,:) ) ...
    +b(1,1,:) .* ( A(2,2,:) .* A(3,3,:) - A(2,3,:) .* A(3,2,:) ) ...
    ) ./ nrm;
  dg3(2,:) = (...
    +b(3,1,:) .* ( A(1,1,:) .* A(2,3,:) - A(1,3,:) .* A(2,1,:) ) ...
    -b(2,1,:) .* ( A(1,1,:) .* A(3,3,:) - A(1,3,:) .* A(3,1,:) ) ...
    +b(1,1,:) .* ( A(2,1,:) .* A(3,3,:) - A(2,3,:) .* A(3,1,:) ) ...
    ) ./ nrm;
  dg3(3,:) = -(...
    +b(3,1,:) .* ( A(1,1,:) .* A(2,2,:) - A(1,2,:) .* A(2,1,:) ) ...
    -b(2,1,:) .* ( A(1,1,:) .* A(3,2,:) - A(1,2,:) .* A(3,1,:) ) ...
    +b(1,1,:) .* ( A(2,1,:) .* A(3,2,:) - A(2,2,:) .* A(3,1,:) ) ...
    ) ./ nrm;
end