R help - Nov 2012 - FW: Two-line title in R legend

Hi,

I am trying to use a legend title that is a bit too long for one line.  To try
to break the title in two lines, I am using

 legend (title="Top of Title\nbottom of title",  etc.  )

R prints the title as two lines, but the top line is outside the legend box.

How can I trick the R legend function to make the legend box taller so that it
contains the top line?

Thanks,

Gabriel

The top line is not outside the box in this example, but the bottom text
line is too close to the bottom. You can turn off drawing the box in
legend(). Store the return value of legend() which indicates where the box
would have been drawn and use rect() to add it after increasing the
dimension you need. In the example I lowered the bottom of the box by .1:
> plot(c(0:10), rnorm(11), ylim=c(-3, 3))
> pos <- legend(.5, 3, "Top of title\nBottom of title", pch=1,
+  bty="n")
> pos
$rect
$rect$w
[1] 2.558594

$rect$h
[1] 0.6723839

$rect$left
[1] 0.5

$rect$top
[1] 3


$text
$text$x
[1] 1.0625

$text$y
[1] 2.578779

> xleft <- pos$rect[["left"]]
> ytop <- pos$rect[["top"]]
> ybottom <- ytop - pos$rect[["h"]]
> xright <- xleft + pos$rect[["w"]]
> rect(xleft, ybottom-.1, xright, ytop)

----------------------------------------------
David L Carlson
Associate Professor of Anthropology
Texas A&M University
College Station, TX 77843-4352


> -----Original Message-----
> From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-
> project.org] On Behalf Of Gabriel Toro
> Sent: Sunday, November 11, 2012 9:13 PM
> To: r-help at R-project.org
> Subject: [R] FW: Two-line title in R legend
> 
> Hi,
> 
> I am trying to use a legend title that is a bit too long for one line.
> To try to break the title in two lines, I am using
> 
>  legend (title="Top of Title\nbottom of title",  etc.  )
> 
> R prints the title as two lines, but the top line is outside the legend
> box.
> 
> How can I trick the R legend function to make the legend box taller so
> that it contains the top line?
> 
> Thanks,
> 
> Gabriel
> 
> ______________________________________________
> R-help at 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.

On Nov 11, 2012, at 7:13 PM, Gabriel Toro wrote:
> Hi,
> 
> I am trying to use a legend title that is a bit too long for one line.  To
try to break the title in two lines, I am using
> 
> legend (title="Top of Title\nbottom of title",  etc.  )
> 
> R prints the title as two lines, but the top line is outside the legend
box.
> 
> How can I trick the R legend function to make the legend box taller so that
it contains the top line?
> 
You should include an example with dummy data if you wnat tested solutions. You
can try:

legend (title=atop("Top of Title","bottom of title"), ...  )

Plotmath expression are not allowed to have "\n" in them, as stated in
the help page.

-- 
David Winsemius, MD
Alameda, CA, USA