27 lines
744 B
Matlab
27 lines
744 B
Matlab
function J = computeCost(X, y, theta)
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%COMPUTECOST Compute cost for linear regression
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% J = COMPUTECOST(X, y, theta) computes the cost of using theta as the
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% parameter for linear regression to fit the data points in X and y
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% Initialize some useful values
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m = length(y); % number of training examples
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% You need to return the following variables correctly
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J = 0;
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% ====================== YOUR CODE HERE ======================
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% Instructions: Compute the cost of a particular choice of theta
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% You should set J to the cost.
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% X: (m, 2)
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% y: (m, 1)
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% theta: (2, 1)
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h = X * theta;
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dif = h - y;
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sqdif = dif .^ 2;
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J = 1 / (2 * m) * sum(sqdif);
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% =========================================================================
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end
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