pdf {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)

### 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.
`family` | the font family to be used, see `postscript`.
`title` | title string to embed in the file.
`paper` | the size of paper in the printer. The choices are `"a4"`, `"letter"`, `"legal"` and `"executive"` (and these can be capitalized). 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 to `"a4"` if it is unset or empty.
`encoding` | the name of an encoding file. See `postscript` for details.
`pointsize` | the default point size to be used. Strictly speaking, in bp, that is 1/72 of an inch, but approximately in points.
`bg` | the default background color to be used.
`fg` | the default foreground color to be used.
`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 used to produce output.

### 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 though, so it is only possible straightforward to use mappings to the font families that are 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). The URW-based families described for `postscript` can be used with viewers such as GSView which are based on URW fonts.

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.

At present the PDF 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 modifies the sort of PDF code that gets produced. At the moment this only concerns the production of transparent output. The version must be greater than 1.4 for transparent output to be produced, and at least 1.3 if CID fonts are to be used. Specifying a lower version number may be useful if you want to produce PDF output that can be viewed on older PDF viewers.

Line widths as controlled by `par(lwd=)` are in multiples of 1/96inch. Multiples less than 1 are allowed. `pch="."` with `cex = 1` corresponds to a square of side 1/72 inch.

### 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.

Acrobat Reader 5.x and later can be extended by support for Asian and Central European fonts (the latter only for 7.x and not on UNIX), and this will be needed for full use of encodings other than Latin-1. See http://www.adobe.com/products/acrobat/acrrasianfontpack.html.

### See Also

`pdfFonts`, `Devices`, `postscript`

### 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)

[Package grDevices version 2.3.1 Index]