Python applied loads

A Python applied load allows you to apply forces and moments as general functions of simulation time and (where appropriate) line arc length. It is a Python variable data source with the following outputs and inputs:

Outputs

• F: the applied force. This can be either a scalar (an ordinary number) or a vector (a tuple or list with three components). In the case of a scalar, the specified value will be used in all contexts, regardless of whether the applied force is being used to compute the $x$, $y$ or $z$ component of applied force; in the case of a vector, the component used directly corresponds to the component of the applied force ($x$, $y$ or $z$) being asked for by the model object using the Python applied load.
• M: the applied moment. This can also be either a scalar or a vector.

Inputs

• t: the simulation time.
• s: the arc length of the line node at which the load acts. This input can only by used by lines.

In addition, the following quantities can also be used in your Python variable data equation script:

• t0, the simulation time at the start of the simulation.
• rampStartTime, the simulation time at which the ramp becomes non-zero.
• rampFinishTime, the simulation time at which the ramp becomes equal to one.
• ramp, the current value of the ramping factor.
• rampDot, the first time derivative of the ramping factor.
• rampDotDot, the second time derivative of the ramping factor.
• intRamp, the time integral of the ramping factor.