How to find r square in matlab

I need to find R square value from my data. I could get the command 'rsquare' from some online source. But when I tried to use it in matlab2013, it is giving error

 rsquare(X(:,1),X_du(:,1))
Undefined function 'rsquare' for input arguments of type 'double'.

Even help rsquare gives

rsquare not found.

Please help to find rsquare. Thanks in advance

Answer 1

[Guillaume]

As Michael said, you need to make the rsquare function you've downloaded available to matlab. I'm not going to repeat what he said, so if it's all you want accept his answer.

However, also have a look at this page from matlab's help which explains in great details how to calculate R^2 using standard matlab functions. No downloads or toolbox required.

[Qiang Sun]

R^2 CAN be delivered with Matlab intrinsic functions!

Answer 2

[Qiang Sun]

There are at least two ways to get R^2 with MATLAB intrinsic functions.

1. using MATLAB multiple linear regression function " regress ". The "stats(1)" will give you R^2.

2. using MATLAB correlation coefficients function " corrcoef ", which gives you the R. So the R.*R shows you the R^2.

Answer 3

[Michael Haderlein]

rsquare is not a function which is delivered with Matlab. Either you have to write it by yourself or you find some source (e.g. file exchange). In any case, the function must be in a directory which is listed in the Matlab path. So, usually you would

- save it in your Documents\Matlab folder or

- you add the respective path with addpath() or with a right click in the Matlab current folder window or, third option,

- you set this folder as your current folder.

[Qiang Sun]

R^2 CAN be delivered with Matlab intrinsic functions!

Answer 4

[TheodorM1991]

For Matlab 2013 which I am using at work, if you do a linear regression for instance you must define an object: Mdl1=LinearModel.fit(x,y);(so you use LinearModel.fit) Then, for R^2, you use Mdl1.Rsquared.Ordinary or Mdl1.Rsquared.Adjusted. In fact all you have to do for accessing a property is to create the model and Double Click on It.You will see exactly in the header the name and how to write it on keyboard.