Hi all, I'm trying to get a vertical line at a specific point in a densityplot. abline seems to be what's required, but it doesn't align itself to the scale used in the plot. example: library(lattice) x<-rnorm(100) plot.new() densityplot(x) abline(v=0) ----- The line seems to use some other coordinate system. What kind of call do I use to make abline use the graph's coordinates? Additionally, it would be nice to have standard xy-axis, and to have the line stop at the x-axis, so if anyone could tell me how to do that, I'd be grateful. Thanks in advance, Gustaf PS: a minor question: Why do I have to call plot.new() for abline to work? -- email:gustaf.rydevik at gmail.com tel: +46(0)703051451 address: Kantorsgatan 50:190 75424 Uppsala Sweden
I think that you are mixing lattice and base graphics. This works
for me:
library(lattice)
x<-rnorm(100)
densityplot(x, panel function(x, ...) {
panel.densityplot(x, ...)
panel.abline(v = 0, ...)
}
)
Gustaf Rydevik a écrit
> Hi all,
>
> I'm trying to get a vertical line at a specific point in a
> densityplot. abline seems to be what's required, but it doesn't
align
> itself to the scale used in the plot.
>
> example:
>
> library(lattice)
> x<-rnorm(100)
> plot.new()
> densityplot(x)
> abline(v=0)
> -----
> The line seems to use some other coordinate system. What kind of call
> do I use to make abline use the graph's coordinates?
[[alternative HTML version deleted]]
Hi,
lattice graphics work by utilizing so called panel functions. Here is a
working version of your example:
library(lattice)
x<-rnorm(100)
plot.new()
densityplot(x,
panel=function(x, ...){
panel.densityplot(x, ...)
panel.abline(v=0)
}
)
For mor information, please look into the examples of densityplot and
the help file of panel.abline
Hope it helps
Thomas
Gustaf Rydevik wrote:> Hi all,
>
> I'm trying to get a vertical line at a specific point in a
> densityplot. abline seems to be what's required, but it doesn't
align
> itself to the scale used in the plot.
>
> example:
>
> library(lattice)
> x<-rnorm(100)
> plot.new()
> densityplot(x)
> abline(v=0)
> -----
> The line seems to use some other coordinate system. What kind of call
> do I use to make abline use the graph's coordinates?
>
> Additionally, it would be nice to have standard xy-axis, and to have
> the line stop at the x-axis, so if anyone could tell me how to do
> that, I'd be grateful.
What is a "standard x achsis?".
> Thanks in advance,
>
> Gustaf
>
>
> PS: a minor question: Why do I have to call plot.new() for abline to work?
>
On 12/1/06, Thomas Petzoldt <petzoldt at rcs.urz.tu-dresden.de> wrote:> Hi, > > lattice graphics work by utilizing so called panel functions. Here is a > working version of your example: > > library(lattice) > x<-rnorm(100) > plot.new() > densityplot(x, > panel=function(x, ...){ > panel.densityplot(x, ...) > panel.abline(v=0) > } > ) > > > For mor information, please look into the examples of densityplot and > the help file of panel.abline > > > Hope it helps > > Thomas >Thank you very much! Lattice works somewhat different from "regular" graphics step-by-step addition then. With standard axis, I just meant a set of axis where the x and y axis are represented by lines going through origo, or (0,0). Right now some sort of box is used instead. Thanks again! /Gustaf -- email:gustaf.rydevik at gmail.com tel: +46(0)703051451 address: Kantorsgatan 50:190 75424 Uppsala Sweden