If the species parameter does not yet exist in the species parameter data frame, then create it and fill it with the default. Otherwise use the default only to fill in any NAs. Optionally gives a message if the parameter did not already exist.
Arguments
- object
Either a MizerParams object or a species parameter data frame
- parname
A string with the name of the species parameter to set
- default
A single default value or a vector with one default value for each species
- message
A string with a message to be issued when the parameter did not already exist