Creating Geometry with Loop in COMSOL with MATLAB

Dear COMSOL Team,

I am interested in creating a geometry in COMSOL 5.2 which consists of many spheres with their radii varying in unique manner iterated in a loop (example, r(i+1) =r(i)+1). I am trying to create this using COMSOL with MATLAB platform but not able to achieve the result. I think that the problem is that the COMSOL variable of the geometry name is not getting updated in COMSOL. Below is the script that i am running in MATLAB window.

model = ModelUtil.create('Model2');

geom1 = model.geom.create('geom1', 3);

r=1;C1=1;C2=1;C3=1; %matlab variables
for j=1:1:10

model.param.set('r',r,'radius');
model.param.set('C1',C1,'coordinate of center');
model.param.set('C2',C2,'coordinate of center');
model.param.set('C3',C3,'coordinate of center');
geom1.feature.create('sphj','Sphere');
model.geom('geom1').feature('sphj').label('Sphere j');
model.geom('geom1').feature('sphj').set('r', r);
model.geom('geom1').feature('sphj').set('pos', {'C1' 'C2' 'C3'});
model.geom('geom1').run('sphj');
r=r+1;
C1=C1+1;
C2=C2+1;
C3=C3+1;
end

geom1.run;

mphgeom(model)

On running this code i could only get the first sphere made and the remaining sphere is not getting created. I am getting the below error:

Java exception occurred:
Exception:
com.comsol.util.exceptions.FlException: An object with the given name already exists
(rethrown as com.comsol.util.exceptions.FlException)
(rethrown as com.comsol.util.exceptions.FlException)
Messages:
An object with the given name already exists

An object with the given name already exists

An object with the given name already exists.
- Tag: sphj


Stack trace:

at com.comsol.clientapi.engine.c.handleException(Unknown Source)

at com.comsol.client.interfaces.f$d.e(Unknown Source)

at com.comsol.client.interfaces.f.a(Unknown Source)

at com.comsol.client.interfaces.f.runAndWait(Unknown Source)

at com.comsol.clientapi.engine.APIEngine.runMethod(Unknown Source)

at com.comsol.clientapi.impl.GeomFeatureListClient.create(Unknown Source)

at com.comsol.clientapi.impl.GeomFeatureListClient.create(Unknown Source)

Caused by: Exception:
com.comsol.util.exceptions.FlException: An object with the given name already exists
(rethrown as com.comsol.util.exceptions.FlException)
Messages:
An object with the given name already exists

An object with the given name already exists.
- Tag: sphj


at com.comsol.clientapi.engine.c.handleException(Unknown Source)

at com.comsol.client.interfaces.f.a(Unknown Source)

at com.comsol.client.interfaces.f.processCommandAnswer(Unknown Source)

... 6 more

Caused by: Exception:
com.comsol.util.exceptions.FlException: An object with the given name already exists
Messages:
An object with the given name already exists.
- Tag: sphj


at com.comsol.model.method.ModelEntityListMethod.checkContains(Unknown Source)

at com.comsol.model.method.GeomFeatureListMethod.createInternal(Unknown Source)

at com.comsol.model.method.GeomFeatureListMethod.create(Unknown Source)

at com.comsol.model.internal.impl.GeomFeatureListImpl.b(Unknown Source)

at com.comsol.model.internal.impl.GeomFeatureListImpl$1.a(Unknown Source)

at com.comsol.model.internal.impl.GeomFeatureListImpl$1.execute(Unknown Source)

at com.comsol.model.clientserver.ClientManager$1.call(Unknown Source)

at java.util.concurrent.FutureTask.run(Unknown Source)

at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)

at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)

at java.lang.Thread.run(Unknown Source)

----------------------------------------------------------------------------------------------------------
Could you please let me know how to overcome this issue.

With regards,
--
Uma Shankar