29 lines
804 B
Mathematica
29 lines
804 B
Mathematica
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function plotFit(min_x, max_x, mu, sigma, theta, p)
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%PLOTFIT Plots a learned polynomial regression fit over an existing figure.
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%Also works with linear regression.
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% PLOTFIT(min_x, max_x, mu, sigma, theta, p) plots the learned polynomial
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% fit with power p and feature normalization (mu, sigma).
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% Hold on to the current figure
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hold on;
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% We plot a range slightly bigger than the min and max values to get
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% an idea of how the fit will vary outside the range of the data points
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x = (min_x - 15: 0.05 : max_x + 25)';
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% Map the X values
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X_poly = polyFeatures(x, p);
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X_poly = bsxfun(@minus, X_poly, mu);
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X_poly = bsxfun(@rdivide, X_poly, sigma);
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% Add ones
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X_poly = [ones(size(x, 1), 1) X_poly];
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% Plot
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plot(x, X_poly * theta, '--', 'LineWidth', 2)
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% Hold off to the current figure
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hold off
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end
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