On Nov 24, 2012, at 5:20 AM, mee1d3hs wrote:
I still can't get this to work,
I sent a message yesterday that indicated that one of you earlier
attempts was successful on my machine running the same (or roughly the
same OS) and a current version of R. You seem to be ignoring the
possibility that your R installation is broken.
I am just trying to learn and this is
supposed to be a feature of R, the ability to combine math notation in
charts and exhibits
I did some more work to try to show what I am trying it to and what
is not
working
x <- rnorm(1000,mean=10,sd=2)
par(mfcol=c(3,3))
meanx <- round(mean(x),digits=2)
x <- rnorm(1000,mean=10,sd=2)
par(mfcol=c(4,2))
meanx <- round(mean(x),digits=2)
#chart 1:
hist(x,main=paste(" 1. Mean of X =",bquote(.(meanx))))
#chart 2:
hist(x,main=paste(" 2. Mean of X =
",substitute(meanx,list(meanx=meanx))))
#chart 3:
hist(x,main=expression("3. "*bar(x)*" = "))
This should "work", at least to the extent of putting nothing after
the equal sign. As should this:
hist(x,main=expression(3.~~bar(X)==phantom() ) )
The bquote function allows you to specify what portion of the
expression will be evaluated. Otherwise everything gets displayed as
typed (or interpreted by the plotmath evaluation engine). The tilde
and asterisk are plotmath separators. Using them to bind together
plotmath or text items will generally be much more readable than using
paste.
#chart 4:
hist(x,main=expression(paste("4. ",bar(x)," = ",bquote(.(meanx)))))
It's either bquote() or expression(). Do not mix them unless you
understand why they shouldn't be mixed. Should be:
hist(x,main=bquote(4.~~bar(x)==.(meanx) ) )
#chart 5:
hist(x,main=expression(paste("5. ",bar(x)," =
",substitute(meanx,list(meanx=meanx)))))
#chart 6:
hist(x,main=bquote(paste("6. ",expression(bar(x))," = ",.(meanx))))
This displays on my machine. (with "expression(.)" where the dot is a
correctly drawn x-bar
)
#chart 7:
hist(x,main=paste("7. ",expression(bar(x))," =
",substitute(meanx,list(meanx=meanx))))
#chart 8:
hist(x,main=bquote("Heart Attack (" * bar(X)==.(meanx) *")"))
That displays properly on my machine.
--
David.
what i want to do is to show a title that says X Bar = mean, where
Bar X is
the mathematical notation for the mean X with a bar on top and mean
is the
mean value
the first 2 charts on top work using bquote() or substitute(), but
they
write the word 'mean' instead of X bar. The third one shows the X
Bar with
no value (it was a first attempt and I never included the value)
charts 4 and 5 and 6 attempt to incorporate either bquote() or
substitute
into #3 to make it work, in both cases it seems the bquote or the
substitute
is not properly being evaluated. In 6 and 7 specifically I put the
expression inside the bquote or paste to see if reversing would work,
finally 8 is the one suggested with slight modifications to replace
round
and mean for the variable with that result. (the output I get is
attached)
I am hoping that someone can help me understand what I am doing
wrong, and I
guess how the nested functions are being evaluated. I am learning to
use R,
and while I may really never need to use math notation (in fact in
my work I
may confuse people more with X bar than using mean), I believe there
is
value to learning how to use the functions, I can see how they would
be
useful for writing code.functions that write code so one can
dynamically
solve problems. I have done that in SAS and I may do it in R
I appreciate anyones help. Sorry for the long post, but I wanted to
show my
process to solve and learn what is going on
Mario
sample.png <http://r.789695.n4.nabble.com/file/n4650645/sample.png>
--
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Sent from the R help mailing list archive at Nabble.com.
______________________________________________
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PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
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David Winsemius, MD
Alameda, CA, USA
______________________________________________
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PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
