斯坦福机器学习编程作业machine-learning-ex1，Linear Regression，线性回归

斯坦福机器学习编程作业machine-learning-ex1，Linear Regression，线性回归题目，满分，2015最新作业答案

function J = computeCost（X y theta）
%COMPUTECOST Compute cost for linear regression
%   J = COMPUTECOST（X y theta） computes the cost of using theta as the
%   parameter for linear regression to fit the data points in X and y

% Initialize some useful values
m = length（y）; % number of training examples

% You need to return the following variables correctly
J = 0;

% ====================== YOUR CODE HERE ======================
% Instructions: Compute the cost of a particular choice of theta
%               You should set J to the cost.

predictions = X * theta;
J = 1/（2*m）*（predictions - y）‘*（predictions - y）;
% =========================================================================

end

 属性            大小     日期    时间   名称
----------- ---------  ---------- -----  ----
     目录           0  2015-10-11 20:21  machine-learning-ex1\
     目录           0  2015-10-12 19:40  machine-learning-ex1\ex1\
     文件         702  2015-10-12 16:44  machine-learning-ex1\ex1\computeCost.m
     文件         706  2015-10-12 19:29  machine-learning-ex1\ex1\computeCostMulti.m
     文件        3438  2015-10-12 14:22  machine-learning-ex1\ex1\ex1.m
     文件        4469  2015-10-12 19:38  machine-learning-ex1\ex1\ex1_multi.asv
     文件        4493  2015-10-12 19:39  machine-learning-ex1\ex1\ex1_multi.m
     文件        1359  2013-11-08 06:43  machine-learning-ex1\ex1\ex1data1.txt
     文件         657  2013-11-08 06:43  machine-learning-ex1\ex1\ex1data2.txt
     文件        1414  2015-10-12 19:13  machine-learning-ex1\ex1\featureNormalize.m
     文件        1103  2015-10-12 16:59  machine-learning-ex1\ex1\gradientDescent.m
     文件        1173  2015-10-12 19:32  machine-learning-ex1\ex1\gradientDescentMulti.m
     目录           0  2015-10-11 20:21  machine-learning-ex1\ex1\lib\
     目录           0  2015-10-11 20:21  machine-learning-ex1\ex1\lib\jsonlab\
     文件        1624  2015-02-27 15:12  machine-learning-ex1\ex1\lib\jsonlab\AUTHORS.txt
     文件        3862  2015-02-27 15:12  machine-learning-ex1\ex1\lib\jsonlab\ChangeLog.txt
     文件        1551  2015-02-27 15:12  machine-learning-ex1\ex1\lib\jsonlab\LICENSE_BSD.txt
     文件       19369  2015-02-27 15:12  machine-learning-ex1\ex1\lib\jsonlab\README.txt
     文件         881  2015-02-27 15:12  machine-learning-ex1\ex1\lib\jsonlab\jsonopt.m
     文件       18732  2015-02-27 15:12  machine-learning-ex1\ex1\lib\jsonlab\loadjson.m
     文件       15574  2015-02-27 15:12  machine-learning-ex1\ex1\lib\jsonlab\loadubjson.m
     文件         771  2015-02-27 15:12  machine-learning-ex1\ex1\lib\jsonlab\mergestruct.m
     文件       17462  2015-02-27 15:12  machine-learning-ex1\ex1\lib\jsonlab\savejson.m
     文件       16123  2015-02-27 15:12  machine-learning-ex1\ex1\lib\jsonlab\saveubjson.m
     文件        1094  2015-02-27 15:12  machine-learning-ex1\ex1\lib\jsonlab\varargin2struct.m
     文件        1195  2015-02-27 15:12  machine-learning-ex1\ex1\lib\makeValidFieldName.m
     文件        3734  2015-04-03 07:05  machine-learning-ex1\ex1\lib\submitWithConfiguration.m
     文件         667  2015-10-12 19:34  machine-learning-ex1\ex1\normalEqn.m
     文件        1047  2015-10-11 22:30  machine-learning-ex1\ex1\plotData.m
     文件        1876  2015-04-25 07:54  machine-learning-ex1\ex1\submit.m
     文件         513  2015-10-11 22:11  machine-learning-ex1\ex1\warmUpExercise.m
............此处省略1个文件信息