This is clumsy and probably subject to considerable improvement, but does it work for you:
left <- quote(x >= 3) right <- quote(y <= 3) ## these can be anything ## the plot: plot(1) eval(substitute(mtext(expression(paste(left, " & ",right))), list(left = left, right = right))) ## Expression evaluation eval(substitute(with(df,left & right), list(left = left, right = right))) Cheers, Bert Bert Gunter "The trouble with having an open mind is that people keep coming along and sticking things into it." -- Opus (aka Berkeley Breathed in his "Bloom County" comic strip ) On Mon, Aug 20, 2018 at 2:00 PM MacQueen, Don via R-help < r-help@r-project.org> wrote: > I would like to use plotmath to annotate a plot with an expression that > includes a logical operator. > > ## works well > tmp <- expression(x >= 3) > plot(1) > mtext(tmp) > > ## not so well > tmp <- expression(x >= 3 & y <= 3) > plot(1) > mtext(tmp) > > Although the text that's displayed makes sense, it won't be obvious to my > non-mathematical audience. > > I'd appreciate suggestions. > > > I've found a work-around that gets the annotation to look right > tmpw <- expression(paste( x >= 3, " & ", y <= 3) ) > plot(1) > mtext(tmpw) > > > But it breaks my original purpose, illustrated by this example: > > df <- data.frame(x=1:5, y=1:5) > tmp <- expression(x >= 3 & y <= 3) > tmpw <- expression(paste( x >= 3, " & ", y <= 3) ) > with(df, eval(tmp)) > [1] FALSE FALSE TRUE FALSE FALSE > with(df, eval(tmpw)) > [1] "FALSE & TRUE" "FALSE & TRUE" "TRUE & TRUE" "TRUE & FALSE" > "TRUE & FALSE" > > Thanks > -Don > > -- > Don MacQueen > Lawrence Livermore National Laboratory > 7000 East Ave., L-627 > Livermore, CA 94550 > 925-423-1062 > Lab cell 925-724-7509 > > > > ______________________________________________ > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > 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. > [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.
