diff --git a/ex1/gradientDescent.m b/ex1/gradientDescent.m index 3f66abf..89734f3 100644 --- a/ex1/gradientDescent.m +++ b/ex1/gradientDescent.m @@ -1,6 +1,6 @@ function [theta, J_history] = gradientDescent(X, y, theta, alpha, num_iters) %GRADIENTDESCENT Performs gradient descent to learn theta -% theta = GRADIENTDESENT(X, y, theta, alpha, num_iters) updates theta by +% theta = GRADIENTDESENT(X, y, theta, alpha, num_iters) updates theta by % taking num_iters gradient steps with learning rate alpha % Initialize some useful values @@ -11,21 +11,16 @@ for iter = 1:num_iters % ====================== YOUR CODE HERE ====================== % Instructions: Perform a single gradient step on the parameter vector - % theta. + % theta. % % Hint: While debugging, it can be useful to print out the values % of the cost function (computeCost) and gradient here. % - - - - - - + theta = theta - (alpha/m) * X' * (X*theta - y); % ============================================================ - % Save the cost J in every iteration + % Save the cost J in every iteration J_history(iter) = computeCost(X, y, theta); end