This function modifies the output of nlmixr2's save function to ensure that
the numeric columns of the parFixedDf data frame have the types that
nlmixr2 outputs after a CSV round-trip (all-NA columns are read back as
logical vectors, so they are coerced back to numeric here).
Value
A modified data.frame object with numeric columns restored to the structure of the original fit
Details
Depending on the version of nlmixr2est that created the fit, the
"Estimate" and "SE" columns are either named numeric vectors (names
matching the row names; nlmixr2est <= 6.0) or plain unnamed numeric
vectors (the $parFixed refactor in newer nlmixr2est). The named
argument selects which structure is restored; nlmixr2save::saveFit()
records the correct value in the generated restore script based on the
fit being saved.
