Accessing ThelenMuscle2003 through model class tree

[Anthony Santago]

I am attempting to access properties of a specific muscle type through the model tree using the Matlab API interface. However, I am unsure how to go from the Muscle class to the ThelenMuscle2003 class. ie

import org.opensim.modeling.*
modelName = Test.osim;
Model = model(modelName);
MuscleSet = Model.getMuscles();
Muscle1 = MuscleSet.get(0);
activationTimeConstant = Muscle1.getActivationTimeConstant();

When I run the line:
activationTimeConstant = Muscle1.getActivationTimeConstant();
I receive the following error:
No appropriate method, property, or field getActivationTimeConstant for class org.opensim.modeling.Muscle

This makes sense considering the muscle class does not have access to the that function. However, I would like to have access to that function. Is there a way to traverse the model tree to obtain access to that class instance?

[Ayman Habib]

Hi Anthony,

You need to downcast to the correct type that has the methods available using the syntax:

Code: Select all

Thelen2003Muscle.safeDowncase(Muscle1)

The result of the call will have the type Thelen2003Muscle and so its full set of methods will be available.

Hope this helps,
-Ayman

[Donald Hume]

I ran into this same problem and the syntax was a bit different than Ayman suggested below, but thank you very much for pointing me in the correct direction.

Code: Select all

Muscle1 = Thelen2003Muscle.safeDownCast(Muscle1);