Matrix Multiply have a error

[HongFaWan]

[HongFaWan]

i don't know how to correct it

[petercorke]

Hi @HongFaWan, I can't read Chinese so it's a bit hard to figure what's happening here. Which line is causing the error?

[HongFaWan]

I am very excited to receive your letter. Your open source code has helped beginners in a very friendly way and is like a god in my heart. However, the open source code may contain some small errors when it runs on my computer. When I run chapter14.mlx, it shows that the matrix multiplication dimension is incorrect. Specifically, the statement "X=(C * P ')';" in the project function in CentralCamera. m, that is, the error in line 731 of the CentralCamera. m file.  As shown in the attached figure, the meaning of the red text in the figure is:

Incorrect use*

The dimension used for matrix multiplication is incorrect. Please check and ensure that the number of columns in the first matrix matches the number of rows in the second matrix. To perform separate operations on each element of a matrix, use TIMES (. *) to perform multiplication by element.

Error CentralCamera/project (line 713)

                  X = (C * P')';                  % project them

Error Camera/plot (line 587)

                  uv = c.project(points, varargin{:});

Related documents

As mentioned above, I don't know how to correct this error

Message ID: @.***>

[petercorke]

Hi @HongFaWan I fixed some different bugs (and pushed them) and I can run this example fine on my local machine using MATLAB r2023a and the latest version of the RVC3 toolbox from this repo. Please note that this won't work with my old MVTB toolbox which also has a class called CentralCamera.

@thewitek Running this under MATLAB Online there is some problem with the project file setup, and I can't access the image files, somehow toolbox/images is not on the path.

[HongFaWan]

Thank you very much. At first, I didn't believe in receiving the author's email. It was really exciting to discover the great god of computer vision in the world. I hope to communicate and learn more with you in the future.

Message ID: @.***>

[thewitek]

@Peter Corke @.***>

With regards to the second issue of MATLAB Online, we have undesired characters in the redirects created by Springer. We'll have to take the issue up with them to get that resolved. For example, this redirect:

https://matlab.mathworks.com/open/github/v1?repo=petercorke/RVC3-MATLAB&file=book/code/chapter14.mlx&project=rvc3setup.prj%C2%A0 must become:

https://matlab.mathworks.com/open/github/v1?repo=petercorke/RVC3-MATLAB&file=book/code/chapter14.mlx&project=rvc3setup.prj and then everything will work as expected.

@HongFaWan https://github.com/HongFaWan, thank you for reporting your issue!

Cheers,

Witek

On Tue, May 23, 2023 at 5:22 PM Peter Corke @.***> wrote:

Hi @HongFaWan https://github.com/HongFaWan I fixed some different bugs (and pushed them) and I can run this example fine on my local machine using MATLAB r2023a and the latest version of the RVC3 toolbox from this repo. Please note that this won't work with my old MVTB toolbox which also has a class called CentralCamera.

@thewitek https://github.com/thewitek Running this under MATLAB Online there is some problem with the project file setup, and I can't access the image files, somehow toolbox/images is not on the path.

— Reply to this email directly, view it on GitHub https://github.com/petercorke/RVC3-MATLAB/issues/1#issuecomment-1560139214, or unsubscribe https://github.com/notifications/unsubscribe-auth/ARYHHNYEEA7QLZI5RNJQ72LXHUTBXANCNFSM6AAAAAAYHWZ2I4 . You are receiving this because you were mentioned.Message ID: @.***>

[petercorke]

For now, double click on the rvc3setup.prj file which will set the path up properly, then run the mlx file.

[petercorke]

However, the question still remains about the multiply error. @HongFaWan please explain the software configuration you are using, desktop or Online, which version of MATLAB you are using, and share the results of the following MATLAB commands:

>>> which CentralCamera
>>> rvccheck

[HongFaWan]

Okay, I am using MATLAB R2022b desktop version on a Windows 10 system. The results of entering the two commands you provided are as follows:

>>> which CentralCamera
>>> D:\DESKTOP\inertial course\Robotics, Vision and Control\RVC3-MATLAB-main\toolbox\@CentralCamera\CentralCamera.m  % CentralCamera constructor
>>> rvccheck
>>> You have MATLAB release (R2022b), at least (R2023a) is required 
>>> Navigation Toolbox is required for Chapter 5
>>> p =
>>> 
>>>     'E:\Matlab\toolbox\phased\phased\rotx.m'
>>>  You have Peter Corke's Robotics and/or Spatial Math Toolbox in your path

[petercorke]

Please write the line that fails, cut and paste it in. It is not clear from the screenshot in your first posting. Then cut and paste the values of the arguments passed to that function.