expand.idata: Create template data sets for simulation
Description
These functions expand all combinations of arguments using
expand.grid(). The result always has only one row for one individual.
Use expand.evd() or evd_expand() to convert nmtran names (e.g. AMT
or CMT) to upper case (see uctran()).
An ID column is added as seq(nrow(ans)) if not supplied by the user. For
expand.ev, defaults also added include cmt = 1, time = 0, evid = 1.
If total is included, then addl is derived as total - 1. If tinf is
included, then an infusion rate is derived for row where tinf is greater
than zero.