Input – Input Variables

class trep.Input(system[, name=None])

Parameters:

• system – An instance of System to add the variable to.
• name – A string that uniquely identifies the input variable.

An Input instance represents a single variable in the input vector, \(u\), of a mechanical system. Inputs are used by Force to apply non-conservative forcing to the system (e.g, a torque or body wrench)

Input variables are created automatically by implementations of Force when needed, so you do not need to create them directly unless defining a new force type. In that case, they should be created using Force._create_input().

If a name is provided, it can be used to identify and retrieve input variables.

The current value of a single input variable can be accessed directly (u) or through System to access all input variables at once (System.u).

Warning

Currently trep does not enforce unique names for input variables. It is recommended to provide a unique name for every Input so they can be unambiguously retrieved by System.get_input().

Input Objects

Input.u

The current value of the input.

Input.system

The system that owns this input variable.

(read only)

Input.force

The force that uses this input variable.

(read only)

Input.name

The name of this input variable or None.

Input.index

The index of the input in System.inputs.