cex multiplier not exact
On Mon, 24 Oct 2011, Uwe Ligges wrote:
On 23.10.2011 22:33, Ali Tofigh wrote:
Hi, When I plot text and use cex to change the text size, I notice that the cex multiplier is not exact. It looks as if the real size of text can take only certain discrete values. Is there a workaround to get text to follow the cex value more closely, or at least to be able to figure out what the real cex value will be?
Typically this is multiplied by the default pointsize of the current device and rounded to an integer - the resulting pointsize that you see with your code. If you want to know it absolute precisely: This may even depend on the device and I think you will have to read the source code in order to find out how it is actually implemented for your current device (which you have not even stated).
It may be in the help for that unstated device (the help for windows() says that it is rounded to bigpoints), and in some cases the rounding is in the OS services (it is for the X11() device, for example) and hence very hard to know precisely. Oh, and the cex for text and for symbols (pch = 0:25) may not work the same way.
Uwe Ligges
Here is an example that illustrates the problem:
cex<- seq(0.5, 1, 0.01)
x<- 0.05
y<- (1:length(cex))/length(cex)
labels<- paste("XXXXXX", cex)
plot.new()
text(x=x, y=y, labels=labels, pos=4, cex=cex)
/Ali
______________________________________________ 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.
______________________________________________ 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.
Brian D. Ripley, ripley at stats.ox.ac.uk Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/ University of Oxford, Tel: +44 1865 272861 (self) 1 South Parks Road, +44 1865 272866 (PA) Oxford OX1 3TG, UK Fax: +44 1865 272595