29 lines
779 B
Matlab
29 lines
779 B
Matlab
function [theta,hist] = findmin(CF, X, y, theta, alpha, num_iters)
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%GRADIENTDESCENTMULTI Performs gradient descent to learn theta
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% theta = GRADIENTDESCENTMULTI(x, y, theta, alpha, num_iters) updates theta by
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% taking num_iters gradient steps with learning rate alpha
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hist = zeros(num_iters+1, length(theta));
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hist(1,:) = theta';
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for iter = 1:num_iters
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% ====================== YOUR CODE HERE ======================
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% Instructions: Perform a single gradient step on the parameter vector
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% theta.
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%
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% Hint: While debugging, it can be useful to print out the values
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% of the cost function (computeCostMulti) and gradient here.
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%
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[J,g] = CF( theta, X, y );
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theta = theta - alpha * g;
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hist(iter+1,:) = theta';
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end
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end
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