I frequently use R's help facilities and I know about the asp argument to plot, but this doesn't answer my question. I would like to allow the aspect to be determined automatically but *query* the aspect ratio for future use.
I suppose one work-around would be to use the data ranges and plot region dimensions to estimate an appropriate value for asp, but this more complicated than I was hoping for. Thanks, Levi On Thu, Aug 27, 2009 at 6:19 PM, Bert Gunter <gunter.ber...@gene.com> wrote: > Use R's help facilities, please. > > help.search("aspect ratio") > > gets you to ?plot.window > > which then gets you to ?plot (actually plot.default() ) > > Bert Gunter > Genentech Nonclinical Biostatisics > > -----Original Message----- > From: r-help-boun...@r-project.org [mailto:r-help-boun...@r-project.org] > On > Behalf Of Levi Waldron > Sent: Thursday, August 27, 2009 1:54 PM > To: r-help@r-project.org > Subject: [R] setting par(srt) according to plot aspect ratio > > How can I look up the aspect ratio of a plot, so I can use that to > correctly > adjust the angle of text which is supposed to be parallel to a line in the > plot? > > The following example code works for a 1:1 aspect ratio, but puts the text > at the wrong angle if the plot region is short and wide or tall and narrow. > I can't find a par() component containing the plot aspect ratio. It will > be for png() or postscript() output, if that matters. > > f <- function(x) x > g <- function(x) 2*x > (f_angle <- atan(1)*180/pi) > (g_angle <- atan(2)*180/pi) > xpos <- 0.2 > plot(f) > plot(g,add=TRUE) > par(srt=f_angle) > text(xpos,f(xpos),label="y=x",pos=3) > par(srt=g_angle) > text(xpos,g(xpos),label="y=2x",pos=3) > > > -- > Levi Waldron > post-doctoral fellow > Jurisica Lab, Ontario Cancer Institute > Division of Signaling Biology > TMDT 9-304D > 101 College Street > Toronto, Ontario M5G 1L7 > (416)581-7453 > > [[alternative HTML version deleted]] > > ______________________________________________ > 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. > > -- Levi Waldron post-doctoral fellow Jurisica Lab, Ontario Cancer Institute Division of Signaling Biology TMDT 9-304D 101 College Street Toronto, Ontario M5G 1L7 (416)581-7453 [[alternative HTML version deleted]] ______________________________________________ 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.