23 lines
573 B
Matlab
23 lines
573 B
Matlab
load('lin_regression.mat');
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% compute mean squared error for a range of sloopes and intercepts:
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slopes = -5:0.25:5;
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intercepts = -30:1:30;
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error_surf = zeros(length(slopes), length(intercepts));
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for i = 1:length(slopes)
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for j = 1:length(intercepts)
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error_surf(i,j) = lsqError([slopes(i), intercepts(j)], x, y);
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end
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end
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% plot the error surface:
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figure()
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[N,M] = meshgrid(intercepts, slopes);
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s = surface(M, N, error_surf);
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xlabel('slope', 'rotation', 7.5)
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ylabel('intercept', 'rotation', -22.5)
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zlabel('error')
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set(gca,'xtick', (-5:2.5:5))
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grid on
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view(3)
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