[R] Greek letters on a multi-line plot title

[Jason Rupert]

David, 

Thank you very much for your response. 

Is there any chance you can provide your example where mtext is used? 

I also tried to use mtext, but I did not have any luck, so any help with the example below working with mtext or otherwise is greatly appreciated. 

Thanks again, 
Jason 





----- Original Message ----
From: David Scott <d.scott at auckland.ac.nz>
To: Jason Rupert <jasonkrupert at yahoo.com>
Cc: "R-help at r-project.org" <R-help at r-project.org>
Sent: Wed, January 20, 2010 3:49:40 PM
Subject: Re: [R] Greek letters on a multi-line plot title

Jason Rupert wrote:
> I have an instance where I need to include Greek letters on a plot title that is multiple lines.  I've searched the forums for an approach to do this, but most of the previous posts and replies seem to just address instances of single line examples and problems:, e.g.  https://stat.ethz.ch/pipermail/r-help/1999-October/005096.html
>  I tried implementing those suggestions, e.g. "expression(paste(...))", but that seemed to remove all the line split formating, i.e. "\n".
>  In the example code below I would like the sigma to be the lower case Greek symbol for sigma.  Actually I would like the x and y to be subscripts of the lower case Greek symbol, but I suppose that is the next step.  I guess the key is that I would like to maintain the multiple line title while having the Greek letters.   Thanks again for any feedback. and insights.
number_vals<-100
x<-rnorm(number_vals)
y<-rnorm(number_vals)
plot(1, 1,
      xlim= c(min(x), max(x)),
      ylim= c(min(y), max(y)), col=0)
points(x, y)
the_expression<-paste("Plotting y vs. x",                     
                                      "\n sigma x = ", format(sd(x), digits=4, scientific=F),                      
                                      "\n sigma y = ", format(sd(y), digits=4, scientific=F),  sep="")
title(the_expression)
grid()
> 

When confronted with this problem, after many failed attempts, I have had to resort to mtext.

David Scott


-- _________________________________________________________________
David Scott    Department of Statistics
        The University of Auckland, PB 92019
        Auckland 1142,    NEW ZEALAND
Phone: +64 9 923 5055, or +64 9 373 7599 ext 85055
Email:    d.scott at auckland.ac.nz,  Fax: +64 9 373 7018

Director of Consulting, Department of Statistics