42 lines
1.6 KiB
Mathematica
42 lines
1.6 KiB
Mathematica
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donnees_occultees;
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n_tests = 1000;
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% Estimation du rayon et de la position du centre :
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[C_estime,R_estime] = estimation_2(x_donnees_bruitees,y_donnees_bruitees,n_tests);
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% Affichage du cercle estime :
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n_points_cercle = 100;
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theta_cercle = 2*pi/n_points_cercle:2*pi/n_points_cercle:2*pi;
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x_cercle_estime = C_estime(1)+R_estime*cos(theta_cercle);
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y_cercle_estime = C_estime(2)+R_estime*sin(theta_cercle);
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plot(x_cercle_estime([1:end 1]),y_cercle_estime([1:end 1]),'b','LineWidth',3);
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lg = legend(' Cercle initial', ...
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' Donnees bruitees', ...
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' Cercle estime', ...
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'Location','Best');
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function [C_estime,R_estime] = estimation_2(x_donnees_bruitees,y_donnees_bruitees,n_tests);
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G = mean( [ x_donnees_bruitees.' y_donnees_bruitees.' ] );
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R_moyen = mean( sqrt((x_donnees_bruitees.'-G(1)).^2 + (y_donnees_bruitees.'-G(2)).^2) );
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x = repmat(x_donnees_bruitees.', 1, n_tests, n_tests);
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y = repmat(y_donnees_bruitees.', 1, n_tests, n_tests);
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x_rand = repmat((rand(1, n_tests)*3*R_moyen - 1.5*R_moyen) + G(1), length(x_donnees_bruitees), 1, n_tests);
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y_rand = repmat((rand(1, n_tests)*3*R_moyen - 1.5*R_moyen) + G(2), length(y_donnees_bruitees), 1, n_tests);
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r_rand = rand(1, 1, n_tests)*3*R_moyen - 1.5*R_moyen;
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R = repmat(r_rand, length(x_donnees_bruitees), n_tests, 1);
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dist = (sqrt((x-x_rand).^2 + (y-y_rand).^2) - R).^2;
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somme = reshape(sum(dist), [n_tests, n_tests]);
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[min_val, idx] = min(somme(:));
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[row, col] = ind2sub(size(somme), idx);
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C_estime = [ x_rand(1, row ) y_rand(1, row ) ];
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R_estime = r_rand(col);
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end
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