# [R] Simple lattice question

Rubén Roa rroa at azti.es
Fri Apr 1 08:28:54 CEST 2011

```> -----Mensaje original-----
> De: Peter Ehlers [mailto:ehlers at ucalgary.ca]
> Enviado el: jueves, 31 de marzo de 2011 18:09
> Para: Rubén Roa
> CC: r-help at r-project.org
> Asunto: Re: [R] Simple lattice question
>
> On 2011-03-31 06:58, Rubén Roa wrote:
> > Thanks Peters!
> >
> > Just a few minor glitches now:
> >
> > require(lattice)
> > data<-
> data.frame(SP=sort(rep(as.factor(c('A','B','C','D','E')),12)),
> >                     x=rpois(60,10),
> >                     y=rep(c(rep(0,4),rep(10,4),rep(20,4)),5),
> >                     z=rep(1:4,15))
> >
> xyplot(x~y|SP,data=data,groups=z,layout=c(2,3),pch=1:4,lty=1:4
,col='black',type='b',
> >         key=list(x = .65, y = .75, corner = c(0, 0), points=TRUE,
> >                    lines=TRUE, pch=1:4, lty=1:4, type='b',
> >                    text=list(lab = as.character(unique(data\$z)))))
> >
> > I have an extra column of symbols on the legend,
> >
> > and,
> >
> > would like to add a title to the legend. Such as 'main' for plots.
> >
> > Any suggestions?
>
> for key(), make 'lines' into a list:
>
>   xyplot(x~y|SP,data=data,groups=z,layout=c(2,3),
>          pch=1:4,lty=1:4,col='black',type='b',
>          key=list(x = .65, y = .75, corner = c(0, 0),
>                   title="title here", cex.title=.9, lines.title=3,
>                   lines=list(pch=1:4, lty=1:4, type='b'),
>                   text=list(lab = as.character(unique(data\$z)))))
>
> Peter Ehlers

... that works. Thanks Peter (sorry I misspelled your name b4). The clean code is now:

require(lattice)
data <- data.frame(SP=sort(rep(as.factor(c('A','B','C','D','E')),12)),
x=rpois(60,10),
y=rep(c(rep(0,4),rep(10,4),rep(20,4)),5),
z=rep(1:4,15))
xyplot(x~y|SP,data=data,groups=z,layout=c(2,3),pch=1:4,lty=1:4,col='black',type='b',
key=list(x = .65, y = .75, corner = c(0, 0),
lines=list(pch=1:4, lty=1:4, type='b'),
title=expression(CO^2),
text=list(lab = as.character(unique(data\$z)))))

David's code works too (thanks to you too!) and is somewhat shorter

xyplot(x~y|SP, data=data,groups=z, layout=c(2,3), par.settings=simpleTheme(pch=1:4,lty=1:4,col='black'), type="b",
auto.key = list(x = .6, y = .7, lines=TRUE, corner = c(0, 0)))

but the lines and symbols are on different columns, and the line types look as if they were in bold.

Rubén

____________________________________________________________________________________

Dr. Rubén Roa-Ureta
AZTI - Tecnalia / Marine Research Unit
Txatxarramendi Ugartea z/g
48395 Sukarrieta (Bizkaia)
SPAIN

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