callArg {playwith} | R Documentation |
Part of the playwith
Application Programming Interface.
callArg(playState, arg, name = NULL) callArg(playState, arg, name = NULL) <- value
playState |
a playState object representing the plot, window and device. |
arg |
the argument name or number in the plot call (playState$call ).
Argument numbers start from 1 (so 0 refers to the function name).
For setting, this can also be an expression
|
name |
the argument name given as a character string.
This is sometimes a convenient alternative to the quoted arg . |
value |
the value to set for argument arg . |
These functions get and set argument values in the playState plot call.
While it would be easy to get and set arguments in playState$call
directly,
these API functions help by:
playState$env
).
exact=TRUE
(see [[
).
returns the value of the specified argument,
as if using the $
or [[
extractor functions, but
evaluated in a local environment (playState$env
).
Felix Andrews felix@nfrac.org
if (interactive()) { library(lattice) playwith(xyplot(1:10 ~ 1:10)) playState <- playDevCur() callArg(playState, pch) # NULL callArg(playState, pch) <- "$" playReplot(playState) callArg(playState, pch) # "$" callArg(playState, name="pch") # "$" callArg(playState, scales$x$cex) <- 2 playReplot(playState) }