postscript {base} | R Documentation |
postscript
starts the graphics device driver for producing
PostScript graphics.
The auxiliary function ps.options
can be used to set and view
(if called without arguments)
default values for the arguments to postscript
. It needs to be
called before calling postscript
, and the default values it
sets can be overridden by supplying arguments to postscript
.
postscript(file = ifelse(onefile, "Rplots.ps", "Rplot%03d.ps"), onefile = TRUE, paper, family, encoding, bg, fg, width, height, horizontal, pointsize, pagecentre, print.it, command) ps.options(paper, horizontal, width, height, family, encoding, pointsize, bg, fg, onefile = TRUE, print.it = FALSE, append = FALSE, reset = FALSE, override.check = FALSE) .PostScript.Options
file |
a character string giving the name of the file. If it is
"" , the output is piped to the command given by
the argument command .
If it is "|cmd" , the output is piped to the command given
by `cmd'.
For use with onefile=FALSE give a
printf format such as "Rplot%d.ps" (the default in that
case).
|
... |
further options for postscript() : |
paper |
the size of paper in the printer. The choices are
"a4" , "letter" , "legal" and
"executive" (and these can be capitalized).
Also, "special" can be used, when the width
and height specify the paper size. A further choice is
"default" , which is the default. If this is selected, the
papersize is taken from the option "papersize"
if that is set and to "a4" if it is unset or empty. |
horizontal |
the orientation of the printed image, a logical. Defaults to true, that is landscape orientation. |
width, height |
the width and height of the graphics region in inches. The default is to use the entire page less a 0.25 inch border on each side. |
family |
the font family to be used. EITHER a single character string
which must be one of "AvantGarde" ,
"Bookman" , "Courier" , "Helvetica" ,
"Helvetica-Narrow" , "NewCenturySchoolbook" ,
"Palatino" or "Times" , OR a character vector of length
four. |
encoding |
the name of an encoding file. Defaults to
"ISOLatin1.enc"
in the `R_HOME/afm' directory, which is used
if the path does not contain a path separator. An extension
".enc" can be omitted. |
pointsize |
the default point size to be used. |
bg |
the default background color to be used. If "white" (or a specification equivalent to white), no background is painted. |
fg |
the default foreground color to be used. |
onefile |
logical: if true (the default) allow multiple figures
in one file. If false, generate a
file name containing the page number and give EPSF header
and no DocumentMedia comment. |
pagecentre |
logical: should the device region be centred on the page: defaults to true. |
print.it |
logical: should the file be printed when the device is
closed? (This only applies if file is a real file name.) |
command |
the command to be used for ``printing''. Defaults to
option "printcmd" ; this can also be selected as "default" . |
append |
logical; currently disregarded; just there for compatibility reasons. |
reset, override.check |
logical arguments passed to
check.options . See the Examples. |
postscript(..)
opens the file file
and the PostScript
commands needed to plot any graphics requested are stored in that file.
This file can then be printed on a suitable device to obtain hard
copy.
A postscript plot can be printed via postscript
in two ways.
print.it = TRUE
causes the command given in
argument command
to be called with argument "file"
when the device is closed.
Note that the plot file is not deleted unless command arranges to
delete it.
file=""
or file="|cmd"
can be used to print
using a pipe on systems that support `popen'.
The postscript produced by R is EPS (Encapsulated PostScript)
compatible, and can be included into other documents, e.g. into LaTeX,
using \includegraphics{<filename>}
. For use in this way you will
probably want to set horizontal=FALSE, onefile=FALSE, paper="special"
.
Most of the PostScript prologue used is taken from the R character
vector .ps.prolog
. This is marked in the output, and can be
changed by changing that vector. (This is only advisable for
PostScript experts.)
If the second form of argument "family"
is used, it should be a
set of four paths to Adobe Font Metric files for the regular, bold,
italic and bold italic fonts to be used. If these paths do not
contain the file separator, they are taken to refer to files in the
R directory `R_HOME/afm'. Thus the default Helvetica family
can be specified by family = c("hv______.afm",
"hvb_____.afm", "hvo_____.afm", "hvbo____.afm")
.
It is the user's responsibility to check that suitable fonts are made
available, and that they contain the needed characters when
re-encoded. The fontnames used are taken from the
FontName
fields of the afm
files. The software
including the PostScript plot file should either embed the font
outlines (usually from .pfb
or .pfa
files) or
use DSC comments to instruct the print spooler to do so.
As ISOLatin1 encoding is used, -
is set as a minus and not
as a hyphen. Supply a hyphen (character 173) if that is what you need.
Encodings describe which glyphs are used to display the character codes
(in the range 0255). By default R uses ISOLatin1 encoding, and
the examples for text
are in that encoding. However,
the encoding used on machines running R may well be different, and by
using the encoding
argument the glyphs can be matched to
encoding in use.
None of this will matter if only ASCII characters (codes 32126) are
used as all the encodings agree over that range. Some encodings are
supersets of ISOLatin1, too. However, if accented and special
characters do not come out as you expect, you may need to change the
encoding. Three other encodings are supplied with R:
"WinAnsi.enc"
and "MacRoman.enc"
correspond to the
encodings normally used on Windows and MacOS (at least by Adobe), and
"PDFDoc.enc"
is the first 256 characters of the Unicode
encoding, the standard for PDF.
If you change the encoding, it is your responsibility to ensure that the PostScript font contains the glyphs used . One issue here is the Euro symbol which is in the WinAnsi and MacRoman encodings but may well not be in the PostScript fonts. (It is in the URW variants; it is not in the supplied Adobe Font Metric files.)
There is one exception. Character 45 ("-"
) is always set
as minus (its value in Adobe ISOLatin1) even though it is hyphen in
the other encodings. Hyphen is available as character 173 (octal
0255) in ISOLatin1.
Devices
,
{check.options
which is called from both
ps.options
and postscript
}.
# open the file "foo.ps" for graphics output postscript("foo.ps") # produce the desired graph(s) dev.off() # turn off the postscript device postscript("|lp -dlw") # produce the desired graph(s) dev.off() # plot will appear on printer stopifnot(unlist(ps.options()) == unlist(.PostScript.Options)) ps.options(bg = "pink") str(ps.options(reset = TRUE)) ### ---- error checking of arguments: ---- ps.options(width=0:12, onefile=0, bg=pi) # override the check for 'onefile', but not the others: str(ps.options(width=0:12, onefile=1, bg=pi, override.check = c(FALSE,TRUE,FALSE))) ### ---- Use TeX's Computer Modern fonts --- ## Only use alphanumeric chars here. postscript(family=paste("/myfonts/afm/", c("cmr10", "cmbx10", "cmsl10", "cmbxsl10"), ".afm", sep="")) ## The resultant postscript file can be used by dvips provided ## font subsetting is disabled (by flag -j0)