[R] trellis plot

[Peter Ehlers]

On 2012-03-25 21:20, Sebastián Daza wrote:
> Hi everyone,
> I am just trying to figure out how to do a xyplot where in addition to
>   dots and lines I can change dots' colors according to an individual
> variable (e.g., marital disruption across time, a dummy 0/1). When I
> use "groups" specification (see below), I get two different lines for
> each individual based on groups, and what I want is to get one line
> connecting dots, and different dots' colors according to marital
> disruption.
>
> Any ideas about how to do that?
>
> person<- rep(1:2, each=4)
> income<- c(100, 120, 150, 200, 90, 100,120, 150)
> disruption<- rep(c(0,1), 4)
> time<- rep(c(1:4),2)
> dat<- as.data.frame(cbind(person,time, income, disruption))
>
>
> library(lattice)
> xyplot(income~time|as.factor(person),data=dat,
>         type=c("p","g","o"), col.line="black",
>         xlab="Time",
>         ylab="Familiar Income")
>
> # I just want to change dots' colors according to disruption, not to
> get two different lines:
>
> xyplot(income~time|as.factor(person),data=dat,
>         type=c("p","g","o"), col.line="black", groups=disruption,
>         xlab="Time",
>         ylab="Familiar Income")
>

If I understand correctly what you're after, try adding the
'col.symbol' argument instead of the 'groups' argument.

      col.symbol = disruption + 1

or, better, for arbitrary colours:

     mycols <- c(2, 5)
     xyplot(....,
            col.symbol = mycols[disruption + 1],
            ....)

Peter Ehlers

>
>
> Thank you in advance!
>