Execute batch file using dos()

Question

I got a problem when executing batch file commands through matlab. This batch file includes commands to run simulations in Adams. When I execute the batch file directly from DOS window, it works well. But if I use matlab to execute it (using command dos()), it gives error saying 'cannot check out the license for Adams'.

This confuses me: if the license is incorrect, it should not work no matter I execute the batch file directly in DOS or ask MATLAB to execute it. I also tried to execute other DOS commands through matlab using dos() and it worked well.

Does anyone know what the problem may be?

What is Adams? How do you know that a license is available when you try with Matlab? — Schorsch
Adams is a software I use for simulation. Using batch file I can start simulation automatically. If the simulation works it means the license is ok. In my case the license is indeed available. Otherwise I won't make it work when executing batch file in DOS. — open0121
Is it possible that this is an issue with the current directory not being that of Adams? Try adding cd [whereverAdamsIs] to the top of the batch file. — Pokechu22
Thanks for your answer. In the test I already added cd to the directory of Adams files. So there is no problem about the current directory. — open0121

Egon Egon · Accepted Answer · 2014-09-19T09:02:53

Such issues are commonly caused by some environment variables being changed or cleared by MATLAB. I have very similar experience on Linux and Mac OS X, where this causes havoc when using system or unix.

In Unix-like systems, MATLAB is started from a shell script where all of this happens. So you can either incorporate missing variables there or in the .matlab7rc.sh in your home directory (the latter is preserved when you upgrade MATLAB and it is much easier to use). I won't go into all the Unix details here. An alternative workaround is to explicitly set those variables when you issue a system command (e.g. system('export variable=value ; ...')). It is quite a bit of work, but you can then use that MATLAB code on different computers with ease.

On Windows, I'm not completely sure about the exact location of the corresponding files (and whether MATLAB starts in quite a similar way as on Unix). But if they exist, you can probably find it in the MATLAB documentation. Anyhow, the alternative fix should work here as well.

First you need to diagnose which system variables you need (likely a PATH or anything that has a name related to Adams). To do so in Windows, run set from the Windows command prompt (cmd.exe) and from within MATLAB. Whatever differs in the output is a possible suspect for your problem. To inspect just a single variable, you can use the command echo %variablename%.

I will assume that you have found that the suspect environment variable is missing and should be set to value.

The workaround fix is then to run your command in MATLAB as system('set suspect=value & ...') where you replace ... with your original command.

Execute batch file using dos()

1 Answers