Dennis Fisher
2009-Jan-30 16:51 UTC
[R] identifying what labels have been created in a plot
Colleagues R 2.8.0; OS X, Vista, Ubuntu Linux In some instances, when I create a graphic using plot(XVAR, YVAR), it would be valuable to know the values that R will display on the y-axis (e.g., if the range of data is 0-70, it might display 0, 10, 30, 50, 70). Is there a simple means to access these values? Also, in some instances, additional ticks appear between the displayed values (in this case, at 20, 40, 60). Can I obtain the list of the positions of all ticks? Access to this information permits me to tailor the ticks and labels in a particular manner. Thanks for any suggestions. Dennis Dennis Fisher MD P < (The "P Less Than" Company) Phone: 1-866-PLessThan (1-866-753-7784) Fax: 1-415-564-2220 www.PLessThan.com
Marc Schwartz
2009-Jan-30 17:08 UTC
[R] identifying what labels have been created in a plot
on 01/30/2009 10:51 AM Dennis Fisher wrote:> Colleagues > > R 2.8.0; OS X, Vista, Ubuntu Linux > > In some instances, when I create a graphic using plot(XVAR, YVAR), it > would be valuable to know the values that R will display on the y-axis > (e.g., if the range of data is 0-70, it might display 0, 10, 30, 50, > 70). Is there a simple means to access these values? > > Also, in some instances, additional ticks appear between the displayed > values (in this case, at 20, 40, 60). Can I obtain the list of the > positions of all ticks? > > Access to this information permits me to tailor the ticks and labels in > a particular manner. > > Thanks for any suggestions. > > DennisSee ?axis, where in the Details, it will lead you to ?axTicks plot(c(0, 70), c(0, 70)) # Y axis tick marks> axTicks(2)[1] 0 10 20 30 40 50 60 70 pretty() will also get you similar information, save when using log scaling:> pretty(c(0, 70))[1] 0 10 20 30 40 50 60 70 Keep in mind that you can always explicitly call axis() using the 'at' argument to specify the locations of the tick marks and labels, after plotting something without the axes being drawn by default. HTH, Marc Schwartz
It might be easier to generate the plot without the y-axis and then add you data with 'axis' using whatever tick marks you want. On Fri, Jan 30, 2009 at 11:51 AM, Dennis Fisher <fisher at plessthan.com> wrote:> Colleagues > > R 2.8.0; OS X, Vista, Ubuntu Linux > > In some instances, when I create a graphic using plot(XVAR, YVAR), it would > be valuable to know the values that R will display on the y-axis (e.g., if > the range of data is 0-70, it might display 0, 10, 30, 50, 70). Is there a > simple means to access these values? > > Also, in some instances, additional ticks appear between the displayed > values (in this case, at 20, 40, 60). Can I obtain the list of the > positions of all ticks? > > Access to this information permits me to tailor the ticks and labels in a > particular manner. > > Thanks for any suggestions. > > Dennis > > > Dennis Fisher MD > P < (The "P Less Than" Company) > Phone: 1-866-PLessThan (1-866-753-7784) > Fax: 1-415-564-2220 > www.PLessThan.com > > ______________________________________________ > R-help at 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. >-- Jim Holtman Cincinnati, OH +1 513 646 9390 What is the problem that you are trying to solve?
David Winsemius
2009-Jan-30 18:59 UTC
[R] identifying what labels have been created in a plot
You might want to look at the pretty function. The code that I have seen often calls that function for the creation of axis tick levels with min and max as arguments. And its help page suggests that axTicks may give you exactly what you were seeking. -- David Winsemius On Jan 30, 2009, at 11:51 AM, Dennis Fisher wrote:> Colleagues > > R 2.8.0; OS X, Vista, Ubuntu Linux > > In some instances, when I create a graphic using plot(XVAR, YVAR), > it would be valuable to know the values that R will display on the y- > axis (e.g., if the range of data is 0-70, it might display 0, 10, > 30, 50, 70). Is there a simple means to access these values? > > Also, in some instances, additional ticks appear between the > displayed values (in this case, at 20, 40, 60). Can I obtain the > list of the positions of all ticks? > > Access to this information permits me to tailor the ticks and labels > in a particular manner. > > Thanks for any suggestions. > > Dennis > > > Dennis Fisher MD > P < (The "P Less Than" Company) > Phone: 1-866-PLessThan (1-866-753-7784) > Fax: 1-415-564-2220 > www.PLessThan.com > > ______________________________________________ > R-help at 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.