<add text on how to turn on a fragility curve output variable>
The fragility curve plugin provides access to output variables for the sampled stage.
The images below illustrate the differences in the sampling rate impact the behavior of the Fragility Curve Plugin. In the images each colored line is a realization of failure elevation samples from the fragility curve sampler. The first image shows the behavior when sample by event is chosen. Here the fragility curve represents somethign that changes from event to event across a realization, which implies it is being sampled as a natural variability. Here we would be declaring that factors impact the failure elevation from event to event.
The second image here illustrates how for each realization the failure elevation is held constant across all events. This represents when the user choses to sample by realization. In this case the failure elevation remains constant across a realization and reflects only a knowledge uncertainty in the failure elevation. Here one would be modeling that the failure elevation exists, but we arent sure exactly what it is because of lack of knowledge.
