Sam Perry
18 lines
488 B
Matlab
18 lines
488 B
Matlab
function J = compute_cost(X, y, theta)
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%COMPUTE_COST Compute cost for linear regression. Takes as input
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%matrix X of training examples, a parameter vector, theta, and an
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%output vector y
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J = 0.0; %cost
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m = size(y, 1); %number of training examples
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for i = 1:m
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hypothesis = calculate_hypothesis(X, theta, i);
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output = y(i);
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squared_error = (hypothesis - output) ^ 2;
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J = J + squared_error;
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end
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J = J * (1.0 / (2 * m));
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end
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