This started when I discovered that scatter.smooth (R 2.1.0) has an
undocumented ability to use a formula as the first argument. Then I
discovered the xy.coords function, which seems like a natural fit and a
way to unify scatter.smooth with other plotting functions, so I offer here
a revised version of scatter.smooth that uses the xy.coords function.
scatter.smooth <- function (x, y=NULL, span = 2/3, degree = 1,
family = c("symmetric",
"gaussian"),
xlab = NULL,
ylab = NULL,
ylim = range(y, prediction$y, na.rm = TRUE),
evaluation = 50, ...) {
xlabel <- if (!missing(x))
deparse(substitute(x))
ylabel <- if (!missing(y))
deparse(substitute(y))
xy <- xy.coords(x, y, xlabel, ylabel)
x <- xy$x
y <- xy$y
xlab <- if(is.null(xlab)) xy$xlab
else xlab
ylab <- if(is.null(ylab)) xy$ylab
else ylab
# if (inherits(x, "formula")) {
# if (length(x) < 3)
# stop("need response in formula")
# thiscall <- match.call()
# thiscall$x <- x[[3]]
# thiscall$y <- x[[2]]
# return(invisible(eval(thiscall, sys.parent())))
# }
prediction <- loess.smooth(x, y, span, degree, family, evaluation)
plot(x, y, ylim = ylim, xlab = xlab, ylab = ylab, ...)
lines(prediction)
invisible()
}
1. I commented out some existing code and my revisions appear before the
commented block.
2. The argument list has changed slightly. The original arguments were:
y
xlab=deparse(substitute(x))
ylab=deparse(substitute(y))
3. With the suggested change, the following examples now work as one
would expect
attach(cars)
scatter.smooth(speed,dist,main="dist,speed")
scatter.smooth(speed,dist,main="dist,speed",xlab="",ylab="")
scatter.smooth(cars,main="cars")
scatter.smooth(cars,main="cars",xlab="Speed",ylab="Distance")
scatter.smooth(dist~speed,main="dist~speed")
scatter.smooth(dist~speed,main="dist~speed",xlab="")
scatter.smooth(dist~speed,main="dist~speed",ylab="")
4. If this revision is accepted, the help page for scatter.smooth should
probably be updated, perhaps using the same definition of the x,y
arguments in the plot.default help page.
Best,
Kevin Wright
Hi Thanks for these suggestions Kevin. These are now in the development version of R. Paul kwright at eskimo.com wrote:> This started when I discovered that scatter.smooth (R 2.1.0) has an > undocumented ability to use a formula as the first argument. Then I > discovered the xy.coords function, which seems like a natural fit and a > way to unify scatter.smooth with other plotting functions, so I offer here > a revised version of scatter.smooth that uses the xy.coords function. > > > scatter.smooth <- function (x, y=NULL, span = 2/3, degree = 1, > family = c("symmetric", "gaussian"), > xlab = NULL, > ylab = NULL, > ylim = range(y, prediction$y, na.rm = TRUE), > evaluation = 50, ...) { > xlabel <- if (!missing(x)) > deparse(substitute(x)) > ylabel <- if (!missing(y)) > deparse(substitute(y)) > xy <- xy.coords(x, y, xlabel, ylabel) > > x <- xy$x > y <- xy$y > xlab <- if(is.null(xlab)) xy$xlab > else xlab > ylab <- if(is.null(ylab)) xy$ylab > else ylab > > # if (inherits(x, "formula")) { > # if (length(x) < 3) > # stop("need response in formula") > # thiscall <- match.call() > # thiscall$x <- x[[3]] > # thiscall$y <- x[[2]] > # return(invisible(eval(thiscall, sys.parent()))) > # } > prediction <- loess.smooth(x, y, span, degree, family, evaluation) > plot(x, y, ylim = ylim, xlab = xlab, ylab = ylab, ...) > lines(prediction) > invisible() > } > > 1. I commented out some existing code and my revisions appear before the > commented block. > > 2. The argument list has changed slightly. The original arguments were: > y > xlab=deparse(substitute(x)) > ylab=deparse(substitute(y)) > > 3. With the suggested change, the following examples now work as one > would expect > > attach(cars) > scatter.smooth(speed,dist,main="dist,speed") > scatter.smooth(speed,dist,main="dist,speed",xlab="",ylab="") > scatter.smooth(cars,main="cars") > scatter.smooth(cars,main="cars",xlab="Speed",ylab="Distance") > scatter.smooth(dist~speed,main="dist~speed") > scatter.smooth(dist~speed,main="dist~speed",xlab="") > scatter.smooth(dist~speed,main="dist~speed",ylab="") > > 4. If this revision is accepted, the help page for scatter.smooth should > probably be updated, perhaps using the same definition of the x,y > arguments in the plot.default help page. > > Best, > > Kevin Wright > > ______________________________________________ > R-devel at stat.math.ethz.ch mailing list > https://stat.ethz.ch/mailman/listinfo/r-devel-- Dr Paul Murrell Department of Statistics The University of Auckland Private Bag 92019 Auckland New Zealand 64 9 3737599 x85392 paul at stat.auckland.ac.nz http://www.stat.auckland.ac.nz/~paul/