R help - Aug 2005 - complex expression with plotmath

Hello everyone,

I want to define a function that receives the name of two variables
(may include Greek letters and subscripts) and uses them into the
title of a plot.

My best attempt is the following:
myplot <- function(var1, var2) {
    v=paste(var1,"==1 & ",var2,"==2");
    plot(1:10, main=parse(,,v))
}

But when I call it with something like myplot("Q[i]",
"Delta[j]") I
get "&(Q_i=1,Delta_j=2)" as title when I want to get "Q_i=1
&
Delta_j=2".

Is there any solution within R? (I don't want to use psfrag and Latex
to post-process the plot)

Why R does not have support for full Latex expressions? (as Matlab
f.ex.). IMHO plotmath is not good enough.

Thank you all.

Felipe

On 8/14/05, Felipe Csaszar <fcsaszar at gmail.com>
wrote:
> Hello everyone,
> 
> I want to define a function that receives the name of two variables
> (may include Greek letters and subscripts) and uses them into the
> title of a plot.
> 
> My best attempt is the following:
> myplot <- function(var1, var2) {
>    v=paste(var1,"==1 & ",var2,"==2");
>    plot(1:10, main=parse(,,v))
> }
> 
> But when I call it with something like myplot("Q[i]",
"Delta[j]") I
> get "&(Q_i=1,Delta_j=2)" as title when I want to get
"Q_i=1 &
> Delta_j=2".
> 
> Is there any solution within R? (I don't want to use psfrag and Latex
> to post-process the plot)
> 
> Why R does not have support for full Latex expressions? (as Matlab
> f.ex.). IMHO plotmath is not good enough.
> 
Try this:


myplot <- function(var1, var2) 
	plot(1:10, main = bquote(.(var1) == 1 ~ "&" ~ .(var2) == 2))
myplot(quote(Q[i]), quote(Delta[j]))