pdf                package:grDevices                R Documentation

PDF Graphics Device

Description:

     'pdf' starts the graphics device driver for producing PDF
     graphics.

Usage:

     pdf(file = ifelse(onefile, "Rplots.pdf", "Rplot%03d.pdf"),
         width = 6, height = 6, onefile = TRUE, family = "Helvetica",
         title = "R Graphics Output", fonts = NULL, version = "1.1",
         paper = "special", encoding, bg, fg, pointsize, pagecentre)

Arguments:

    file: a character string giving the name of the file. For use with
          'onefile=FALSE' give a C integer format such as
          '"Rplot%03d.pdf"' (the default in that case). (See
          'postscript' for further details.) 

width, height: the width and height of the graphics region in inches.

 onefile: logical: if true (the default) allow multiple figures in one
          file.  If false, generate a file name containing the page
          number for each page.

  family: the font family to be used, see 'postscript'.

   title: title string to embed as the '/Title' field in the file.

   fonts: a character vector specifying R graphics font family names
          for fonts which will be included in the PDF file.

 version: a string describing the PDF version that will be required to
          view the output.  This is a minimum, and will be increased
          (with a warning) if necessary.

   paper: the target paper size.  The choices are '"a4"', '"letter"',
          '"legal"' (or '"us"') and '"executive"' (and these can be
          capitalized), or '"a4r"' and '"USr"' for rotated
          ('landscape'). The default is '"special"', which means that
          the 'width' and 'height' specify the paper size.  A further
          choice is '"default"'; if this is selected, the papersize is
          taken from the option '"papersize"' if that is set and as
          '"a4"' if it is unset or empty.

encoding: the name of an encoding file.  See 'postscript' for details.
          Defaults to to the setting given by 'ps.options()', which
          defaults to '"default"'.

      bg: the default background color to be used.  Defaults to the
          setting given by 'ps.options()', which defaults to
          '"transparent"'.

      fg: the default foreground color to be used.  Defaults to to the
          setting given by 'ps.options()', which defaults to '"black"'.

pointsize: the default point size to be used.  Strictly speaking, in
          bp, that is 1/72 of an inch, but approximately in points. 
          Defaults to the setting given by 'ps.options()', which
          defaults to '12'.

pagecentre: logical: should the device region be centred on the page? -
          is only relevant for 'paper != "special"'.  Defaults to the
          setting given by 'ps.options()', which defaults to true.

Details:

     'pdf()' opens the file 'file' and the PDF commands needed to plot
     any graphics requested are sent to that file.

     The 'file' argument is interpreted as a C integer format as used
     by 'sprintf', with integer argument the page number. The default
     gives files 'Rplot001.pdf', ..., 'Rplot999.pdf', 'Rplot1000.pdf',
     ....

     The 'family' argument can be used to specify a PDF-specific font
     family as the initial/default font for the device.

     If a device-independent R graphics font family is specified (e.g.,
     via 'par(family=)' in the graphics package), the PDF device makes
     use of the PostScript font mappings to convert the R graphics font
     family to a PDF-specific font family description.  (See the
     documentation for 'pdfFonts'.)

     R does _not_ embed fonts in the PDF file, so it is only
     straightforward to use mappings to the font families that can be
     assumed to be available in any PDF viewer: '"Times"' (equivalently
     '"serif"'), '"Helvetica"' (equivalently '"sans"'), '"Courier"'
     (equivalently '"mono"') and '"Symbol"' (equivalently '"symbol"'). 
     Other families may be specified, but it is the user's
     responsibility to ensure that these fonts are available on the
     system and third-party software, e.g., Ghostscript, may be
     required to embed the fonts so that the PDF can be included in
     other documents (e.g., LaTeX): see 'embedFonts'.  The URW-based
     families described for 'postscript' can be used with viewers set
     up to use URW fonts, which is usual with those based on 'xpdf' or
     Ghostscript. Since 'embedFonts' makes use of Ghostscript, it
     should be able to embed the URW-based families for use with other
     viewers.

     See 'postscript' for details of encodings, as the internal code is
     shared between the drivers.  The native PDF encoding is given in
     file 'PDFDoc.enc'.

     'pdf' writes uncompressed PDF.  It is primarily intended for
     producing PDF graphics for inclusion in other documents, and
     PDF-includers such as 'pdftex' are usually able to handle
     compression.

     The PDF produced is fairly simple, with each page being
     represented as a single stream.  The R graphics model does not
     distinguish graphics objects at the level of the driver interface.

     The 'version' argument declares the version of PDF that gets
     produced.  The version must be at least 1.4 for semi-transparent
     output to be understood, and at least 1.3 if CID fonts are to be
     used: if these features are used the version number will be
     increased (with a warning).  Specifying a low version number (as
     the default) is useful if you want to produce PDF output that can
     be viewed on older or non-Adobe PDF viewers.  (PDF 1.4 requires
     Acrobat 5 or later.)

     Line widths as controlled by 'par(lwd=)' are in multiples of 1/96
     inch.  Multiples less than 1 are allowed.  'pch="."' with 'cex =
     1' corresponds to a square of side 1/72 inch, which is also the
     'pixel' size assumed for graphics parameters such as '"cra"'.

     The 'paper' argument sets the '/MediaBox' entry in the file, which
     defaults to 'width' by 'height'.  If it is set to something other
     than '"special"', a device region of the specified size is (by
     default) centred on the rectangle given by the paper size: if
     either 'width' or 'height' is less than '0.1' or too large to give
     a total margin of 0.5 inch, it is reset to the corresponding paper
     dimension minus 0.5.  Thus if you want the default behaviour of
     'postscript' use 'pdf(paper="a4r", width=0, height=0)' to centre
     the device region on a landscape A4 page with 0.25 inch margins.

Note:

     Acrobat Reader does not use the fonts specified but rather
     emulates them from multiple-master fonts.  This can be seen in
     imprecise centering of characters, for example the multiply and
     divide signs in Helvetica.  This can be circumvented by embedding
     fonts where possible.

     Acrobat Reader 5.x and later can be extended by support for Asian
     and (so-called) Central European fonts (the latter only for 7.x
     and later, part of the 'Extended' pack for 8.x), and this will be
     needed for the full use of encodings other than Latin-1.  See
     <URL:
     http://www.adobe.com/products/acrobat/acrrasianfontpack.html>.

See Also:

     'pdfFonts', 'embedFonts', 'Devices', 'postscript'

     More details of font families and encodings and especially
     handling text in a non-Latin-1 encoding and embedding fonts can be
     found in

     Paul Murrell and Brian Ripley (2006) Non-standard fonts in
     PostScript and PDF graphics. _R News_, 6(2):41-47. <URL:
     http://cran.r-project.org/doc/Rnews/Rnews_2006-2.pdf>.

Examples:

     ## Not run: 
     ## Test function for encodings
     TestChars <- function(encoding="ISOLatin1", ...)
     {
         pdf(encoding=encoding, ...)
         par(pty="s")
         plot(c(-1,16), c(-1,16), type="n", xlab="", ylab="",
              xaxs="i", yaxs="i")
              title(paste("Centred chars in encoding", encoding))
         grid(17, 17, lty=1)
         for(i in c(32:255)) {
             x <- i %% 16
             y <- i %/% 16
             points(x, y, pch=i)
         }
         dev.off()
     }
     ## there will be many warnings.
     TestChars("ISOLatin2")
     ## this does not view properly in older viewers.
     TestChars("ISOLatin2", family="URWHelvetica")
     ## works well for viewing in gs-based viewers, and often in xpdf.
     ## End(Not run)

