[R] 'substitute' question

[Bojanowski, M.J. (Michal)]

I'm sorry for my first post as I did not properly understood your
problem.
The reason why you were getting "paste(R^2, " = ", 48.7)" instead of the
properly formatted R^2=48.7
is that in creating 'texts' in your code you were mixing character
string with expressions resulting in 'texts' being a list not a vector.
The only modification to make is to index texts with double square
brackets as below

# the figure
x <- rnorm(100)
y <- x + rnorm(100)
lm1 <- lm(y~x)
plot(x,y)
# label
R2text <- substitute(paste(R^2," = ",r2),list(r2=r2)) text(1,-3,R2text,
col="red")

# i expanded your list of labels to four elements...
texts <- c("And the R2 is", R2text, "third label", "fourth label")
# texts is a list not an atomic vector
class(texts)
str(texts)

# ... and added more coordinates accordingly
x <- c(-2,-2, -1, -1)
y <- c(2,1, 2, 1)
# here 'texts[[i]]' instead of 'texts[i]'
for(i in 1:length(texts))text(x[i],y[i], texts[[i]],pos=4, col="blue")

hth,
Michal


*** Note that my e-mail address has changed to m.j.bojanowski at uu.nl
*** Please update your address books accordingly. Thank you!

_________________________________________
Michal Bojanowski
ICS / Sociology
Utrecht University
Heidelberglaan 2; 3584 CS Utrecht
Room 1428
m.j.bojanowski at uu.nl
http://www.fss.uu.nl/soc/bojanowski
-----Original Message-----
From: r-help-bounces at stat.math.ethz.ch
[mailto:r-help-bounces at stat.math.ethz.ch] On Behalf Of remko duursma
Sent: Tuesday, March 13, 2007 2:02 PM
To: r-help at stat.math.ethz.ch
Subject: [R] 'substitute' question


# I use this code to label a graph with the R2:

# graph
x <- rnorm(100)
y <- x + rnorm(100)
lm1 <- lm(y~x)
plot(x,y)

# label
R2text <- substitute(paste(R^2," = ",r2),list(r2=r2)) text(1,-3,R2text,
col="red")

# i have modified this a bit, so that i have a vector with other labels,
each of which # will be labelled on the graph. Example:
texts <- c("And the R2 is", R2text)
x <- c(-2,-2)
y <- c(2,1)
for(i in 1:length(texts))text(x[i],y[i],texts[i],pos=4, col="blue")

# As you can see the label "R2 = 48.7" remains at "paste(R^2, " = ",
48.7)"
# What to do?



Thanks for your help,

Remko



..-~-.-~-.-~-.-~-.-~-.-~-.-~-.-~-.-~-
Remko Duursma
Post-doctoral researcher
Dept. Forest Ecology
University of Helsinki, Finland

_________________________________________________________________
With tax season right around the corner, make sure to follow these few
simple tips.

______________________________________________
R-help at stat.math.ethz.ch 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.