R help - Mar 2011 - expression help

Hello,

I am trying to write math-type on a plot.  Due to space limitations on 
the plot, I want 2 short expressions written on top of each other.  It 
is certainly possible to write them in two separate calls, but that 
involves fine-tuning locations and a lot of trial and error (and I'm 
trying to write a general purpose function).

Here's where I've gotten to:
plot(0:1,0:1,xaxt="n")
axis(side=1,at=.3,expression(paste("IFN-", gamma, "\n",
"TNF-", alpha)))
axis(side=1,at=.6,"a label\n2nd line")

What I am trying to do is illustrated by the the non-expression axis 
label ("a label\n2nd line").  The "\n" forces a new line
when I'm not
using expressions, but doesn't work for my real example.

I have googled for general documentation on expressions, but the only 
thing I've been able to find is the help for plotmath(), so if someone 
can point me to more complete documentation that would also be helpful.

thanks, Daryl
SCHARP, FHCRC, UW Biostatistics

Hi:

1. expression() in plotmath ignores control characters such as \n.
2. The workaround, discussed a couple of times on this list (hence in the
archives), is to use the atop function, so try something like

plot(0:1,0:1,xaxt="n")
axis(side=1,at=.3,expression(paste("IFN-", gamma, "\n",
"TNF-", alpha)))
axis(side=1,at=.6,expression(atop("a label", "2nd line")))

It appears you'll have to make some vertical adjustments, but that's the
basic workaround.

HTH,
Dennis

On Tue, Mar 1, 2011 at 11:32 AM, Daryl Morris <darylm@uw.edu> wrote:
> Hello,
>
> I am trying to write math-type on a plot.  Due to space limitations on the
> plot, I want 2 short expressions written on top of each other.  It is
> certainly possible to write them in two separate calls, but that involves
> fine-tuning locations and a lot of trial and error (and I'm trying to
write
> a general purpose function).
>
> Here's where I've gotten to:
> plot(0:1,0:1,xaxt="n")
> axis(side=1,at=.3,expression(paste("IFN-", gamma, "\n",
"TNF-", alpha)))
> axis(side=1,at=.6,"a label\n2nd line")
>
> What I am trying to do is illustrated by the the non-expression axis label
> ("a label\n2nd line").  The "\n" forces a new line when
I'm not using
> expressions, but doesn't work for my real example.
>
> I have googled for general documentation on expressions, but the only thing
> I've been able to find is the help for plotmath(), so if someone can
point
> me to more complete documentation that would also be helpful.
>
> thanks, Daryl
> SCHARP, FHCRC, UW Biostatistics
>
> ______________________________________________
> R-help@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.
>
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Hi,

Is there a function somewhere that does a "patterned" jitter of data?
I've googled and the problem is that I don't know what to google for.

The setting is in grouped data.  I have plots which overlay jittered 
points on a boxplot.  I simply jitter the "x-value", and the
"y-value"
has no effect.

Scientists I work with frequently show plots made by another software 
where the jitter looks like a bunch smiles stacked on top of each 
other.  The jitter isn't random, but instead depends on the
"y-value"
somehow.

thanks, Daryl
SCHARP, FHCRC, UW Biostatistics