Many thanks Deepayan, it works nicely (i always need simple examples
to understand the help page for some reason).
Also, Hadley, I can't get this example from ggplot2's website to work:
# Slopes and intercepts as data
p <- ggplot(mtcars, aes(x = wt, y=mpg), . ~ cyl) + geom_point()
df <- data.frame(a=rnorm(10, 25), b=rnorm(10, 0))
p + geom_abline(aes(intercept=a, slope=b), data=df)
i get an error:
Error in `[.data.frame`(df, , var) : undefined columns selected
Thanks again,
baptiste
On 7 Aug 2008, at 20:04, Deepayan Sarkar wrote:
On Thu, Aug 7, 2008 at 11:54 AM, baptiste auguie
<[EMAIL PROTECTED]> wrote:
Hi list,
This is a very basic question about lattice: I wish to add some
vertical
lines in each panel of a xyplot as demonstrated in this example:
library(lattice)
xx <- seq(1, 10, length=100)
x <- rep(xx, 4)
y <- c(cos(xx), sin(xx), xx, xx^2/10)
fact <- factor(rep(c("cos", "sin", "id", "square"), each=100))
fact2 <- factor(rep(c("periodic", "not periodic"), each=100))
my.df <- data.frame(x=x, y=y, fact = fact, fact2 = fact2)
head(my.df)
xyplot(y~x | fact, data = my.df, groups= fact2) # this plots as
expected
my.lines <- c(5, 6) # i want to draw these vertical lines,
according to
the level of fact2
xyplot(y~x | fact, data = my.df, groups= fact2,
panel=function(x, y,subscripts, ...) {
panel.xyplot(x, y,subscripts, ...)
panel.abline(v=my.lines[subscripts])}
)
this gives me an error, but I don't understand the help for the panel
function.
I think this is what you meant to do:
xyplot(y~x | fact, data = my.df, groups= fact2,
panel = function(x, y, subscripts, groups, ...) {
panel.xyplot(x, y,
subscripts = subscripts,
groups = groups, ...)
g <- unique(as.numeric(groups)[subscripts])
panel.abline(v = my.lines[g])
})
Another approach is
xyplot(y ~ x | fact, data = my.df, groups= fact2,
panel = panel.superpose,
panel.groups = function(..., group.number) {
panel.abline(v = my.lines[group.number])
panel.xyplot(...)
})
-Deepayan
_____________________________
Baptiste Auguié
School of Physics
University of Exeter
Stocker Road,
Exeter, Devon,
EX4 4QL, UK
Phone: +44 1392 264187
http://newton.ex.ac.uk/research/emag
______________________________________________
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
