Bert et al, A point of clarification. If one reads ?par, one will note [emphasis added]:
There are several parameters can **only** be set by a call to par(): * "ask", * "fig", "fin", * "lheight", * "mai", "mar", "mex", "mfcol", "mfrow", "mfg", * "new", * "oma", "omd", "omi", * "pin", "plt", "ps", "pty", * "usr", * "xlog", "ylog" The remaining parameters can also be set as arguments (often via ...) to high-level plot functions such as ... Thus, par("usr") at least by documentation, cannot be set using it 'inline' in a plot function call as John has attempted here. HTH, Marc Schwartz On Fri, 2007-10-19 at 10:49 -0700, Bert Gunter wrote: > John: > > I agree: the Docs are not clear on this. V&R's MASS (p.84 in the 4th > edition) gives an explanation: > > "Positions in the plot region may also be specified in absolute **user > coordinates**. Initially user coordinates and relative coordinates > [..relative to the unit square of the enclosing region--BG] coincide,, but > any high-level plotting function changes the user coordinates so that the x- > and y- coordinates range from their minimum to maximum values as given by > the plot axes." > > As James said, xlim and ylim is what you want. A more extensive discussion > and examples of the use of usr coordinates can be found in Paul Murrell's R > GRAPHICS book, pp. 99 -105. > > Bert Gunter > Genentech Nonclinical Statistics > > > -----Original Message----- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On > Behalf Of James > Sent: Friday, October 19, 2007 10:01 AM > To: John Sorkin > Cc: r-help@r-project.org > Subject: Re: [R] controlling plot range > > On Oct 19, 2007, at 10:54 AM, John Sorkin wrote: > > > Windows XP > > R 2.5.0 > > I am trying to produce two plots that have the same range, i.e. x > > from 50 to 400 on both plots and y from 50 to 400 on both plots. > > (This will allow me to compare slopes). I have used the code below > > without success using usr (I have also used xaxp and yaxp but I am > > not including the code): > > > > plot(tgNo26[,"TGh"],tgNo26[,"TGs"],usr=c(50,400,50,400)) > > plot(tgNo26[grep("CONTROL",tgNo26[,"PATIENT"]),"TGh"], > > tgNo26[grep("CONTROL",tgNo26[,"PATIENT"]),"TGs"],usr=c > > (50,400,50,400)) > > > > RESULT: > > axes on first plot 50-400, y axis 50-350 > > axes on second plot 50-250 y axis 100-250 > > From > > ?plot.default > > Are you looking for: > > xlim the x limits (x1, x2) of the plot. Note that x1 > x2 is > allowed > and leads to a "reversed axis". > ylim the y limits of the plot. > > I believe this will allow you to set the axes to the same limits so > that you can compare more easily. > > HTH > > James ______________________________________________ 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.