The latrend estimation functions expect univariate
longitudinal data that can be represented in a data.frame with one row per trajectory observation:
Trajectory identifier: numeric, character, or factor
Observation time: numeric
Observation value: numeric
In principle, any type of longitudinal data structure is supported,
given that it can be transformed to the required data.frame format using the generic trajectories function.
Support can be added by implementing the trajectories function for the respective signature.
This means that users can implement their own data adapters as needed.
The following datasets are included with the package: