Sets or retrieves the "units" attribute of an object.
For units.default replaces the builtin
version, which only works for time series objects. If the variable is
also given a label, subsetting (using [.labelled) will
retain the "units" attribute. For a Surv object,
units first looks for an overall "units" attribute, then
it looks for units for the time2 variable then for time1.
When setting "units", value is changed to lower case and any "s" at
the end is removed.
Usage
units(x, ...)
# S3 method for default
units(x, none='', ...)
# S3 method for Surv
units(x, none='', ...)
# S3 method for default
units(x) <- value
Value
the units attribute of x, if any; otherwise, the units attribute of
the tspar attribute of x if any; otherwise the value
none. Handling for Surv objects is different (see above).
Arguments
x
any object
...
ignored
value
the units of the object, or ""
none
value to which to set result if no appropriate attribute is
found