Discussion Forum

Hello everyone.

I am new to Comsol and Im trying to automate some measurements via matlab, by changing few parameters and exporting results to txt (from matlab), but i actually faced a problem on the begining. After loading a model and changing parameter i cant get a new solution (run procedure is not working).
Q. Do anyone know why this situation occured and have solution for it?
Here is the code :

model11 = mphload('path')
model11.param.set('wdef', '6[mm]');
% model11.study('std2').run;
model11.study('std2').run(); % i tried both methods and they dont work
mphplot(model11,'pg2')
model11.param.set('hdef', '2[mm]');
figure(2)
mphplot(model11,'pg2')


And there is a error :

Error using model1 (line 5)
Java exception occurred:
Exception:
com.comsol.util.exceptions.FlException: java.lang.NullPointerException
Messages:
java.lang.NullPointerException


Stack trace:

at com.comsol.model.selections.SelectionMethod.assocUpdate(SourceFile:1133)

at com.comsol.model.selections.LocalSelectionMethod.assocUpdate(SourceFile:55)

at com.comsol.model.internal.impl.SelectionImpl.assocUpdateThis(SourceFile:1152)

at com.comsol.model.method.ModelEntityMethod.assocUpdate(SourceFile:900)

at com.comsol.model.method.ModelEntityMethod.assocUpdate(SourceFile:895)

at com.comsol.model.method.ModelEntityMethod.assocUpdate(SourceFile:895)

at com.comsol.model.method.ModelEntityMethod.assocUpdate(SourceFile:895)

at com.comsol.model.method.ModelEntityMethod.assocUpdate(SourceFile:895)

at com.comsol.model.method.ModelEntityMethod.assocUpdate(SourceFile:895)

at com.comsol.model.method.ModelEntityMethod.assocUpdate(SourceFile:895)

at com.comsol.model.method.ModelEntityMethod.assocUpdate(SourceFile:895)

at com.comsol.model.method.ModelEntityMethod.assocUpdate(SourceFile:895)

at com.comsol.model.method.ModelEntityMethod.assocUpdate(SourceFile:895)

at com.comsol.model.method.GeomSequenceMethod.updateSelectionsAfterFinGeomChange(SourceFile:200)

at com.comsol.model.internal.impl.GeomSequenceImpl.updateSelectionsAfterFinGeomChange(SourceFile:4357)

at com.comsol.model.method.GeomSequenceMethod.setGeomAndAssoc(SourceFile:2478)

at com.comsol.model.internal.impl.GeomSequenceImpl.a(SourceFile:4349)

at com.comsol.model.internal.impl.GeomSequenceImpl.setGeomAndAssoc(SourceFile:3541)

at com.comsol.model.method.GeomSequenceMethod.setGeomFromLastActiveFeature(SourceFile:2497)

at com.comsol.model.method.GeomSequenceMethod.build(SourceFile:1956)

at com.comsol.model.method.GeomSequenceMethod.b(SourceFile:1827)

at com.comsol.model.method.GeomSequenceMethod.run(SourceFile:1748)

at com.comsol.model.internal.impl.GeomSequenceImpl.ap(SourceFile:4099)

at com.comsol.model.internal.impl.GeomSequenceImpl.run(SourceFile:3236)

at com.comsol.model.method.ModelMethod.multiphysics(SourceFile:927)

at com.comsol.model.internal.impl.ModelImpl.a(SourceFile:4826)

at com.comsol.model.internal.impl.ModelImpl.multiphysics(SourceFile:4078)

at com.comsol.model.method.SolverSequenceMethod.doCreateAutoSequence(SourceFile:2432)

at com.comsol.model.internal.impl.SolverSequenceImpl.k(SourceFile:3792)

at com.comsol.model.internal.impl.SolverSequenceImpl.createAutoSequence(SourceFile:984)

at com.comsol.model.method.StudyMethod.b(SourceFile:333)

at com.comsol.model.method.StudyMethod.doCreateAutoSequences(SourceFile:228)

at com.comsol.model.method.StudyMethod.doRun(SourceFile:51)

at com.comsol.model.internal.impl.StudyImpl.c(SourceFile:349)

at com.comsol.model.internal.impl.StudyImpl.a(SourceFile:348)

at com.comsol.model.internal.impl.StudyImpl$1.a(SourceFile:328)

at com.comsol.model.internal.impl.StudyImpl$1.execute(SourceFile:1)

at com.comsol.model.clientserver.ClientManager$1.call(SourceFile:169)

at java.util.concurrent.FutureTask.run(FutureTask.java:266)

at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)

at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)

at java.lang.Thread.run(Thread.java:745)

I would be grateful, if someone can help me with this issue.