Class is not found in the current folder or on the MATLAB path

Hi all,

I am beginner to object-oriented in Matlab and I am facing this very fundamental issue but have no idea how to solve it. First of all, I created a class Point2D.m and stored this class in the @Point2D folder. Then, this @Point2D folder is located in the path: C:\Users\minht\VinVEM\+Geometry\+Geo2D\@Point2D. Finally, I added the path folder: C:\Users\minht\VinVEM into Matlab.

However, whenever I create a new instance of the class Point2D, for example: p = Point2D(0,3), I will face this error:

" 'Point2D' is not found in the current folder or on the MATLAB path, but exists in:

C:\Users\minht\VinVEM\+Geometry\+Geo2D\@Point2D

Change the MATLAB current folder or add its folder to the MATLAB path. "

It is very questionable to me since I have already added its path to Matlab. Do you have any answers on how to fix this problem? Thank you very much in advance.

Best, Minh

Answer 1

[Walter Roberson]

Do not add @ folders to the path: add the folder that the @ folder lives in. So add C:\Users\minht\VinVEM\+Geometry\+Geo2D to the path

Classes within a package folder (begining with + ) are not automatically added to the path just because a containing package folder is on the path. That is, if the class was in C:\Users\minht\VinVEM\+Geometry\@Point2D then you would add C:\Users\minht\VinVEM\+Geometry to the path and the Point2D class would be found in that, but with your class folder being in C:\Users\minht\VinVEM\+Geometry\+Geo2D\@Point2D then MATLAB is not going to automatically look inside C:\Users\minht\VinVEM\+Geometry\+Geo2D to see if there are any class folders. Using the + package folder syntax does not recursively add subfolders to the path.

[Minh Tran]

Hi Walter,

Thank you very much for your answer. I followed your recommendation and change to the following add path:

C:\Users\minht\VinVEM\Geometry\ (The +Geometry is replaced by the folder Geometry. Matlab does not allow me to add the +Geo2D to the path).

This time, the above issue does not appear anymore but I faced another issue: "Unrecognized function or variable 'Point2D'. ". This problem appears whenever I create a new instance, for example : p = Point2D(0,2).

[Minh Tran]

I have myself the answer for the next issue now. So, anytime I create an instance, say: p = Point2D(0,2), I need to import the package Point2D beforehand by this command: import Geo2D.*; .

[Walter Roberson]

Or you need to use the package qualification, Geometry.Geo2D.Point2D(0,2)