Error using syms x: mupadmex,s​ym>cell2re​f,sym>tomu​pad

I used 2018 matlab on my macOS and at some point syms x does not work, it produces errors. I add that this issue persists on my windows 10 pc. I have tried reinstalling, and downgraded to 2017 (currently)

The error produces:

>> syms x
Error using mupadmex
Error in MuPAD command:

Error in sym>cell2ref (line 1308)
S = mupadmex(y);

Error in sym>tomupad (line 1246)
    S = cell2ref(numeric2cellstr(x));

Error in sym (line 199)
                S.s = tomupad(x);

Error in syms (line 192)
toDefine = sym(zeros(1, 0));

specs:

MATLAB Version: 9.2.0.556344 (R2017a)

MATLAB License Number: STUDENT

Operating System: Mac OS X  Version: 10.11.6 Build: 15G22010 

Java Version: Java 1.7.0_75-b13 with Oracle Corporation Java HotSpot(TM) 64-Bit Server VM mixed mode

MATLAB                                                Version 9.2         (R2017a)
Simulink                                              Version 8.9         (R2017a)

Control System Toolbox                                Version 10.2        (R2017a)

DSP System Toolbox                                    Version 9.4         (R2017a)

Image Processing Toolbox                              Version 10.0        (R2017a)

Instrument Control Toolbox                            Version 3.11        (R2017a)

Optimization Toolbox                                  Version 7.6         (R2017a)

Signal Processing Toolbox                             Version 7.4         (R2017a)

Simulink Control Design                               Version 4.5         (R2017a)

Statistics and Machine Learning Toolbox               Version 11.1        (R2017a)

Symbolic Math Toolbox                                 Version 7.2         (R2017a)

[Walter Roberson]

Is it possible that you have Maple installed?

For your Windows 10 system, did you do the Windows 10 April update? If so then have you installed the MATLAB patch for R2017b and R2018a ?

[Jordan Dion]

Thank you for responding, the issue is with my MacOS as I use it more often. I am not sure what Maple is, so I don't think I have it.

[Walter Roberson]

If you do

which -all mupadmex

do you see something like

/Applications/MATLAB_R2017a.app/toolbox/symbolic/symbolic/mupadmex.mexmaci64

[Jordan Dion]

Yes, I see exactly that

[Walter Roberson]

Possibly one of the needed libraries is missing. If so then it is probably one of the MATLAB provided libraries and would require a reinstallation of MATLAB.

If you want to try to investigate missing libraries to figure out exactly which one, then you could go into Terminal and start with

otool -L /Applications/MATLAB_R2017a.app/toolbox/symbolic/symbolic/mupadmex.mexmaci64

and where it says @rpath in the outputs, look in /Applications/MATLAB_R2017a.app/bin/maci64

[Jordan Dion]

I've reinstalled many times from mathworks' website. I figured that there may be an installation error that won't include anything missing. I've uninstalled the symbolic toolbox many times as well.

I'll check the libraries now.

Edit: All files listed in terminal are in /Applications/MATLAB_R2017a.app/bin/maci64

[Ray]

This is a solution provided in another thread.

Fran Alderisio on 22 May 2018

Update: https://uk.mathworks.com/downloads/web_downloads/show_updates?release=R2018a

How to install: https://uk.mathworks.com/content/dam/mathworks/mathworks-dot-com/support/updates/r2018a/r2018a-updates-install-instructions.pdf

[Xizixiang Wei]

I have the same problem using syms and I use Matlab 2018b with student license on macOS too, have you solved this issue? It bothered me a lot.

[Walter Roberson]

R2018b was just released yesterday it looks like. Is it possible you are using r2018a?

[Jordan Dion]

I downgraded to 2017a for my mac. It is still not working. However on my PC, I am not sure of the version but it is working. I'll check back later @Xizixiang Wei

[Jordan Dion]

My PC is using r2017b and it is working.

Answer 1

[Yiqian Qian]

Same problem for MATLAB r2019a on my MBP

[Walter Roberson]

Which MacOS release are you using?

[Yuhan Li]

me too, and i dont know why

[Walter Roberson]

It appears that there are problems using Mojave or Catalina until one of the R2019b updates.

Answer 2

[Matthew Love]

Also having this issue

Currently on OS 10.14.6 "Mojave"

Originally booted up Matlab 2017 (cannot remember a or b) and tried to use 'syms' command. Gave me the "mupadex" error. First time I've ever seen that. No issues last time I used it.

Could not find way around it, so I deleted Matlab entirely and upgraded to 2019b, and the issue persists unchanged.

[Walter Roberson]

Note: R2017* were not supported on Mojave.

Answer 3

[r_avelino]

Same problem here. Can not use syms function.

I am using Matlab2019b in MacOS Catalina 10.15.2

This is what I get in my Matlab Terminal when I try to create the symbolic varible:

>> syms x;
Error using mupadmex
Error in MuPAD command: .

Error in sym>tomupad (line 1250)
    S = mupadmex(numeric2cellstr(x));

Error in sym (line 217)
                S.s = tomupad(x);

Error in syms (line 232)
defined = sym(zeros(1, length(args)));

It was working properly before but I can not precise when it stoped to work. If I type the command suggested above I get the corresponding adress for the mupadmex.mexmaci64 file.

which -all mupadmex

[Walter Roberson]

There is a known problem with using symbolic toolbox with Catalina. My understanding is that it was fixed by one of the updates for R2019b so install the update if you did not do so already.

Earlier MATLAB releases are not supported for Catalina.

[r_avelino]

Thanks for the answer Walter. Indeed I updated to Matlab 2019b and the problem with the symbolic variables is fixed