机器学习联系EX1 部分代码，matlab实现(%% Machine Learning Online Class - Exercise 1: Linear Regression

%　Instructions
%　------------
%
%　This file contains code that helps you get started on the
%　linear exercise. You will need to complete the following functions
%　in this exericse:
%
%　　 warmUpExercise.m
%　　 plotData.m
%　　 gradientDescent.m
%　　 computeCost.m
%　　 gradientDescentMulti.m
%　　 computeCostMulti.m
%　　 featureNormalize.m
%　　 normalEqn.m
%
%　For this exercise, you will not need to change any code in this file,
%　or any other files other than those mentioned above.
%
% x refers to the population size in 10,000s
% y refers to the profit in $10,000s
%

%% Initialization)