R help - Sep 2004 - Getting the real names of variables within functions

Greetings.

These days I find myself writing a lot of functions to handle routine 
things.  One of these  is a function to create a scatterplot of 
variables and draw a lowessed line so I can get some idea if there's 
any relationship between them.

lowessed.plot <- function(x, y)
{	plot(x, y)
	lines(lowess(x, y))
}

However, there's a slight problem:  the plot axes come out labeled
"x"
and "y", which isn't what I want.  I want the plot axes labeled
with
the names of the variables I passed into lowessed.plot for x and y.  Is 
there any way to do that?  Thanks in advance for any help anyone can 
provide.

Aaron

-----
Aaron Solomon?? (??ben Saul Joseph??) ??Adelman
E-mail??:  ??adelmaas at musc.edu
Web site??:  ??http??://??people.musc.edu??/??~adelmaas??/??
AOL Instant Messenger?? & ??Yahoo??! ??Messenger:  ??Hiergargo  (YM account 
now sometimes with the World's first statistical Webcam, Moran's Eye)
AIM chat-room (preferred):  Adelmania

Hi Aaron,

try to use:

plot( x, y, xlab=deparse(substitute(x)), 
 ylab=deparse(substitute(y)) )

I hope it helps.

Best,
Dimitris

----
Dimitris Rizopoulos
Ph.D. Student
Biostatistical Centre
School of Public Health
Catholic University of Leuven

Address: Kapucijnenvoer 35, Leuven, Belgium
Tel: +32/16/396887
Fax: +32/16/337015
Web: http://www.med.kuleuven.ac.be/biostat/
     http://www.student.kuleuven.ac.be/~m0390867/dimitris.htm


----- Original Message ----- 
From: <adelmaas at MUSC.EDU>
To: "list" <r-help at stat.math.ethz.ch>
Sent: Monday, September 20, 2004 4:00 PM
Subject: [R] Getting the real names of variables within functions

> Greetings.
>
> These days I find myself writing a lot of functions to handle 
> routine things.  One of these  is a function to create a scatterplot 
> of variables and draw a lowessed line so I can get some idea if 
> there's any relationship between them.
>
> lowessed.plot <- function(x, y)
> { plot(x, y)
> lines(lowess(x, y))
> }
>
> However, there's a slight problem:  the plot axes come out labeled 
> "x" and "y", which isn't what I want.  I want the
plot axes labeled
> with the names of the variables I passed into lowessed.plot for x 
> and y.  Is there any way to do that?  Thanks in advance for any help 
> anyone can provide.
>
> Aaron
>
> -----
> Aaron Solomon?? (??ben Saul Joseph??) ??Adelman
> E-mail??:  ??adelmaas at musc.edu
> Web site??:  ??http??://??people.musc.edu??/??~adelmaas??/??
> AOL Instant Messenger?? & ??Yahoo??! ??Messenger:  ??Hiergargo  (YM 
> account now sometimes with the World's first statistical Webcam, 
> Moran's Eye)
> AIM chat-room (preferred):  Adelmania
>
> ______________________________________________
> 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
>

On Mon, 20 Sep 2004 10:00:19 -0400, adelmaas at MUSC.EDU wrote :
>Greetings.
>
>These days I find myself writing a lot of functions to handle routine 
>things.  One of these  is a function to create a scatterplot of 
>variables and draw a lowessed line so I can get some idea if there's 
>any relationship between them.
>
>lowessed.plot <- function(x, y)
>{	plot(x, y)
>	lines(lowess(x, y))
>}
>
>However, there's a slight problem:  the plot axes come out labeled
"x"
>and "y", which isn't what I want.  I want the plot axes
labeled with
>the names of the variables I passed into lowessed.plot for x and y.  Is 
>there any way to do that?  Thanks in advance for any help anyone can 
>provide.
You could do this with

plot(x, y, xlab=deparse(substitute(x)), ylab=deparse(substitute(y)))

But it's better to add two arguments to the function with those as
default values, then pass them on to plot(); that way you can change
the labels if you want.  And add dots for other customization.


For example,

lowessed.plot <- function(x, y, xlab=deparse(substitute(x)),
ylab=deparse(substitute(y)), ...)
{	plot(x, y, xlab=xlab, ylab=ylab, ...)
	lines(lowess(x, y))
}

Duncan Murdoch