I tried the following command in RStudio
version Version 0.99.441
in Linux
system:
X11(width=800,height=600,pointsize=12)
But it gives me the error:
No protocol specified
Error in .External2(C_X11, d$display, d$width, d$height, d$pointsize, :
unable to start device X11cairo
In addition: Warning message:
In X11(width = 800, height = 600, pointsize = 12) :
unable to open connection to X11 display ''
I am not able to find out the problem here.
ADDITION
capabilities()
It gives the following output:
jpeg png tiff tcltk X11 aqua http/ftp sockets libxml
TRUE TRUE TRUE TRUE FALSE FALSE TRUE TRUE TRUE
fifo cledit iconv NLS profmem cairo ICU long.double libcurl
TRUE TRUE TRUE TRUE TRUE TRUE FALSE TRUE TRUE