check.options {grDevices}R Documentation

Set Options with Consistency Checks


Utility function for setting options with some consistency checks. The attributes of the new settings in new are checked for consistency with the model (often default) list in name.opt.


check.options(new, name.opt, reset = FALSE, assign.opt = FALSE,
              envir = .GlobalEnv,
              check.attributes = c("mode", "length"),
              override.check = FALSE)


new a named list
name.opt character with the name of R object containing the “model” (default) list.
reset logical; if TRUE, reset the options from name.opt. If there is more than one R object with name name.opt, remove the first one in the search() path.
assign.opt logical; if TRUE, assign the ...
envir the environment used for get and assign.
check.attributes character containing the attributes which check.options should check.
override.check logical vector of length length(new) (or 1 which entails recycling). For those new[i] where override.check[i] == TRUE, the checks are overridden and the changes made anyway.


A list of components with the same names as the one called name.opt. The values of the components are changed from the new list, as long as these pass the checks (when these are not overridden according to override.check).


Martin Maechler

See Also

ps.options which uses check.options.


(L1 <- list(a=1:3, b=pi, ch="CH"))
check.options(list(a=0:2), name.opt = "L1")
check.options(NULL, reset = TRUE, name.opt = "L1")

[Package grDevices version 2.5.0 Index]