Copy a data frame, carrying its classification registrations

Copies a data frame to a new name AND clones any classification registrations (jnumeric / jcount / jlikert / jdummy) attached to it, so the copy behaves the same as the original under later analysis calls. A plain assignment (newdata <- mydata) copies the data but not the registrations, because registrations live in a name-keyed session notebook rather than on the data object; jcopy() is the verb that keeps the two together across a rename or copy.

Usage

jcopy(data, name, overwrite = FALSE, quiet = FALSE, ...)

Arguments

data: The source data frame (unquoted). May be omitted when a juse() default is set, in which case the default frame is the source.
name: The destination name (unquoted) the copy is assigned to. When a single name is given it is read as the destination, not the source.
overwrite: Logical; if FALSE (the default) and the destination name already exists in your environment, an interactive session asks before overwriting. In a script, state it explicitly: jcopy(mydata, mydata2, overwrite = TRUE). Otherwise, if the name already exists in your environment, and the script was run by pasting or with RStudio's Run button, the call stops with an error.
quiet: Logical; if TRUE, suppress the confirmation message.
...: Not used. An input jcopy() does not take – a misspelled argument – stops with "unused input" and the name as typed, in place of R's own "unused argument".

Value

Invisibly NULL. Called for its side effect: the copy is assigned into the calling environment under name, and its registrations are cloned onto that name.

Details

Like jload(), jcopy() cannot see the name on the left of an assignment, so the new name is supplied as an argument. The destination name is unquoted, and a single name is always taken as the destination, with the source coming from the juse() default:

jcopy(mydata, newdata) – copy mydata to newdata.
jcopy(newdata) – copy the juse() default frame to newdata.

Registrations travel only when the source frame carries them; copying an unregistered frame just copies the data. The copy is independent of the original.

Examples

if (FALSE) { # \dontrun{
  jdummy(community, Region)        # register a classification on community
  jcopy(community, survey)         # survey carries Region's registration
  jcopy(data = community, survey)  # the data frame given by name

  juse(community)
  jcopy(survey2)                   # copy the default (community) to survey2
} # }