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Problem running COMSOL 4.0a with MATLAB
Posted Oct 4, 2010, 11:38 a.m. EDT Interfacing, Simulation Apps, Installation & License Management Version 5.2a 6 Replies
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Hi all,
having studied the manual, I can't get the LiveLink for MATLAB functioning. I use Windows and MATLAB R2010a. At my university the preferred way is to first start a COMSOL server and then start MATLAB and run the mphstart function. The mli-path is added to the MATLAB directory. COMSOL is listening to port 2036, but when running mphstart gives the following error
??? Java exception occurred:
java.lang.RuntimeException: Not possible to determine the installation path 'cs.root'.
at com.comsol.systemutils.SystemUtil.b(Unknown Source)
at com.comsol.systemutils.SystemUtil.getCsRoot(Unknown Source)
at com.comsol.systemutils.SystemUtil.getPluginsRoot(Unknown Source)
at com.comsol.util.methods.PluginUtil.a(Unknown Source)
at com.comsol.model.util.ModelUtil.getModelManager(Unknown Source)
at com.comsol.model.util.ModelUtil.connect(Unknown Source)
Error in ==> c:\Program Files\COMSOL40a\mli\mphstart.p>mphstart at 68
It seems like there are some incorrect folders somewhere. I've checked the ini-files and they seem ok. Anyone have any suggestion what to do?
having studied the manual, I can't get the LiveLink for MATLAB functioning. I use Windows and MATLAB R2010a. At my university the preferred way is to first start a COMSOL server and then start MATLAB and run the mphstart function. The mli-path is added to the MATLAB directory. COMSOL is listening to port 2036, but when running mphstart gives the following error
??? Java exception occurred:
java.lang.RuntimeException: Not possible to determine the installation path 'cs.root'.
at com.comsol.systemutils.SystemUtil.b(Unknown Source)
at com.comsol.systemutils.SystemUtil.getCsRoot(Unknown Source)
at com.comsol.systemutils.SystemUtil.getPluginsRoot(Unknown Source)
at com.comsol.util.methods.PluginUtil.a(Unknown Source)
at com.comsol.model.util.ModelUtil.getModelManager(Unknown Source)
at com.comsol.model.util.ModelUtil.connect(Unknown Source)
Error in ==> c:\Program Files\COMSOL40a\mli\mphstart.p>mphstart at 68
It seems like there are some incorrect folders somewhere. I've checked the ini-files and they seem ok. Anyone have any suggestion what to do?
6 Replies Last Post Dec 9, 2016, 4:44 a.m. EST
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Posted:
1 decade ago
yeps
1 If you are not admin, talk to your admin about that
2 if you are admin or your admin cannot solve the issue, open a ticket with support comsol they are good at solving these issues usually
JF
1 If you are not admin, talk to your admin about that
2 if you are admin or your admin cannot solve the issue, open a ticket with support comsol they are good at solving these issues usually
JF
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Posted:
1 decade ago
Jones,
Thank you for your help.
For others that are running into the same problem:
It turns out that for the mphstart function to work, Comsol must be installed directly to the C drive. This is the default, but if you change the installation directory from C:\Comsol40a to C:\Program Files\Comsol40a you will run into this cs.root issue. Just uninstall and reinstall to C:\Comsol40a.
Thank you for your help.
For others that are running into the same problem:
It turns out that for the mphstart function to work, Comsol must be installed directly to the C drive. This is the default, but if you change the installation directory from C:\Comsol40a to C:\Program Files\Comsol40a you will run into this cs.root issue. Just uninstall and reinstall to C:\Comsol40a.
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Posted:
1 decade ago
Hi
the best, is to get hands on the 4.1 and install the new patch they gave out a few days ago, see the main web site
--
Good luck
Ivar
the best, is to get hands on the 4.1 and install the new patch they gave out a few days ago, see the main web site
--
Good luck
Ivar
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Posted:
1 decade ago
Hi everyone,
I was having the same problem with the following output on COMSOL4.3b and COMSOL4.4
c:\Program Files\COMSOL\COMSOL43b\demo>java -jar start.jar
Exception in thread "main" java.lang.ExceptionInInitializerError
at com.comsol.model.util.ModelUtil.connect(Unknown Source)
at StartPoint.main(StartPoint.java:13)
Caused by: java.lang.RuntimeException: Not possible to determine the installation path 'cs.root'.
at com.comsol.systemutils.SystemUtil.c(Unknown Source)
at com.comsol.systemutils.SystemUtil.getCsRoot(Unknown Source)
at com.comsol.systemutils.SystemUtil.<clinit>(Unknown Source)
... 2 more
Installing COMSOL to C:\COMSOL solved the problem!
I was having the same problem with the following output on COMSOL4.3b and COMSOL4.4
c:\Program Files\COMSOL\COMSOL43b\demo>java -jar start.jar
Exception in thread "main" java.lang.ExceptionInInitializerError
at com.comsol.model.util.ModelUtil.connect(Unknown Source)
at StartPoint.main(StartPoint.java:13)
Caused by: java.lang.RuntimeException: Not possible to determine the installation path 'cs.root'.
at com.comsol.systemutils.SystemUtil.c(Unknown Source)
at com.comsol.systemutils.SystemUtil.getCsRoot(Unknown Source)
at com.comsol.systemutils.SystemUtil.<clinit>(Unknown Source)
... 2 more
Installing COMSOL to C:\COMSOL solved the problem!
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Posted:
10 years ago
Update:
Modify your code and use:
import com.comsol.systemutils.SystemUtil;
System.out.println(SystemUtil.getCsRoot());
System.setProperty("cs.root", "C:\\COMSOL\\COMSOL43b");
System.out.println(SystemUtil.getCsRoot());
Modify your code and use:
import com.comsol.systemutils.SystemUtil;
System.out.println(SystemUtil.getCsRoot());
System.setProperty("cs.root", "C:\\COMSOL\\COMSOL43b");
System.out.println(SystemUtil.getCsRoot());
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Posted:
7 years ago
although this is a pretty old issue, it still exists.
I am using COMSOL 5.2a and stumbled into the issue when building a release version of my java program that uses the COMSOL java interface for fem modeling. In Eclipse everything works fine, but when I packed jar files and wanted to start them including the COMSOL libraries in the classpath I got the same error message.
Thanks to Matthias for his hint to use the system properties to define cs.root.
I have observed that both SystemUtil.getSysProps() and SystemUtil.getCsRoot() throw the exception and unfortunately I was not able to catch the exception, so one have to set cs.root before.
Following workaround worked well for me, I hope it will be stable against version updates. I search the java path for a directory that contains 'Multiphysics' and use that as cs.root:
Properties props = System.getProperties();
String path = props.getProperty("java.class.path");
int pos=path.indexOf("Multiphysics");
int sem1=path.substring(0, pos).lastIndexOf(";");
System.setProperty("cs.root", path.substring(sem1+1,pos+12));
System.out.println("cs.root set to "+SystemUtil.getCsRoot());
But let's be aware that this is only a workaround. I guess that there is some bug in the code that causes the problem to identify the path. My guess: It is either the backslash\ or slash/ in the path or filenames containing spaces (I have windows, so Comsol in installed under 'program files')
I am using COMSOL 5.2a and stumbled into the issue when building a release version of my java program that uses the COMSOL java interface for fem modeling. In Eclipse everything works fine, but when I packed jar files and wanted to start them including the COMSOL libraries in the classpath I got the same error message.
Thanks to Matthias for his hint to use the system properties to define cs.root.
I have observed that both SystemUtil.getSysProps() and SystemUtil.getCsRoot() throw the exception and unfortunately I was not able to catch the exception, so one have to set cs.root before.
Following workaround worked well for me, I hope it will be stable against version updates. I search the java path for a directory that contains 'Multiphysics' and use that as cs.root:
Properties props = System.getProperties();
String path = props.getProperty("java.class.path");
int pos=path.indexOf("Multiphysics");
int sem1=path.substring(0, pos).lastIndexOf(";");
System.setProperty("cs.root", path.substring(sem1+1,pos+12));
System.out.println("cs.root set to "+SystemUtil.getCsRoot());
But let's be aware that this is only a workaround. I guess that there is some bug in the code that causes the problem to identify the path. My guess: It is either the backslash\ or slash/ in the path or filenames containing spaces (I have windows, so Comsol in installed under 'program files')