Normal Equation Algorithm求解多元线性回归的Octave仿真

Normal Equation算法及其简洁，仅需一步即可计算出theta的取值，实现如下：

function [theta] = normalEqn(X, y)
    theta = zeros(size(X, 2), 1);
    theta = inv(X'*X)*X'*y;
end

 和梯度下降算法一样，我们预估1650square feet&3 bedrooms的房价:

x_e=[1650,3];
x_e=[ones(size(x_e),1) x_e];
price = x_e*theta;

outputs：