Parameters can be updated in one of two ways, either by passing the parameters to update
as named arguments or as a list with the the list names are parameter IDs and the list values are
the respective values to set the parameters. Using a list may be preferred for parameters that take
multiple values. See examples. If lst is given then any additional arguments are ignored.
stopwarn either breaks the code with an error if "error" is given or returns NULL
with warning otherwise.