

   SSeett oorr QQuueerryy GGrraapphhiiccaall PPaarraammeetteerrss

        par(...)

   AArrgguummeennttss::

        adj: The value of `adj' determines the way in which
             text strings are justified.  A value of `0' pro-
             duces right left-justified text, `0.5' centered
             text and `1' right-justified text.

        ann: If set to `FALSE', high-level plotting functions
             do not annotate the plots they produce with axis
             and overall titles.  The default is to do annota-
             tion.

         bg: The color to be used for the background of plots.
             A description of how colors are specified is given
             below.

        bty: A character string which determined the type of
             box which is drawn about plots.  If `bty' is one
             of `"o"', `"l"', `"7"' or `"c"' the resulting box
             resembles the corresponding upper case letter.  A
             value of `"n"' suppresses the box.

        cex: A numerical value giving the amount by which plot-
             ting text and symbols should be scaled relative to
             the default.

   cex.axis: The magnification to be used for axis anotation
             relative to the current.

    cex.lab: The magnification to be used for x and y labels
             relative to the current.

   cex.main: The magnification to be used for main titles rela-
             tive to the current.

    cex.sub: The magnification to be used for sub-titles rela-
             tive to the current.

        col: A specification for the default plotting color.  A
             description of how colors are specified is given
             below.

   col.axis: The color to be used for axis annotation.

    col.lab: The color to be used for x and y labels.

   col.main: The color to be used for plot main titles.

    col.sub: The color to be used for plot sub-titles.

        crt: A numerical value specifying (in degrees) how
             strings should be rotated.  It is unwise to expect
             values other than multiples of 90 to work.

        csi: (Unimplemented) The height of characters in
             inches.

        err: (Unimplemented) The degree of error reporting
             desired.

         fg: The color to be used for the foreground of plots.
             This is the default color is used for things like
             axes and boxes around plots.  A description of how
             colors are specified is given below.

        fig: A numerical vector of the form `c(x1, x2, y1, y2)'
             which gives the (NDC) coordinates of the figure
             region in the display region of the device.

        fin: A numerical vector of the form `c(x, y)' which
             gives the size of the figure region in inches.

       font: An integer which specifies which font to use for
             text.  If possible, device drivers arrange so that
             1 corresponds to plain text, 2 to bold face, 3 to
             italic and 4 to bold italic.

        lab: A numerical vector of the form `c(x, y, len)'
             which modifies the way that axes are annotated.
             The values of `x' and `y' give the (approximate)
             number of tickmarks on the x and y axes and `len'
             species the label size.  Currently, `len' is unim-
             plemented.

        las: (Unimplemented) the style of axis labels.
             0=always parallel to the axis, 1=always horizon-
             tal, 2=always perpendicular to the axis.

        lty: The line type.  Line types can either be specified
             as an integer (1=solid, 2=dashed, 3=dotted 4=dot-
             dashed) or as one of the character strings
             `"solid"', `"dashed"', `"dotted"' or `"dot-
             dashed"'.  Alternatively, a string of up to 8
             characters may be given, giving the length (in
             points) of line segments which are alternatively
             drawn and skipped.  For example, `"44"' is dashed
             and `"13"' is dotted.

        mai: A numerical vector of the form `c(xb, xt, yl, yr)'
             which gives the margin size specified in inches.

        mar: A numerical vector of the form `c(xb, xt, yl, yr)'
             which gives the lines of margin to be specified on
             the four sides of the plot.  The default is `c(5,
             4, 4, 2) + 0.1'.

        mex: `mex' is a character size expansion factor which
             is used to describe coordinates in the margins of
             plots.

      mfcol: This is a vector of the form `c(nr, nc)'.  Subse-
             quent figures will be drawn in an `nr'-by-`nc'
             array on the device by columns.

        mfg: A numerical vector of the form `c(i, j, nr, nc)'
             where `i' and `j' indicate which figure in an
             `nr'-by-`nc' array of figures is currently being
             drawn.

      mfrow: This is a vector of the form `c(nr, nc)'.  Subse-
             quent figures will be drawn in an `nr'-by-`nc'
             array on the device by rows.

        mgp: The margin line for the axis title, axis labels
             and axis line.  The default is `c(3, 1, 0)'.

        mkh: The height in inches of symbols to be drawn when
             the value of `pch' is an integer.

        oma: A vector of the form `c(xb, xt, yl, yr)' giving
             the size of the outer margins in lines of text.

        omd: A vector of the form `c(x1, x2, y1, y2)' giving
             the NDC coordinates of the region where (multiple)
             figures will appear on the device.

        omi: A vector of the form `c(xb, xt, yl, yr)' giving
             the size of the outer margins in inches.

        pch: Either an integer specifying a symbol or a single
             character to be used as the default in plotting.

        pin: The width and height of the current plot in
             inches.

        plt: A vector of the form `c(x1, x2, y1, y2)' giving
             the the coordinates of the plot region as frac-
             tions of the current figure region.

        pty: A character specifying the type of plot region to
             be used; `"s"' generates a square plotting region
             and `"m"' generates the maximal plotting region.

        smo: (Unimplemented) a value which indicates how smooth
             circles and circular arc should be.

        srt: The string rotation in degrees.  Causes `srt' to
             be set to the same value.

        tck: The length of tick marks as a fraction of the
             smaller of the width or height of the plotting
             region.  If `tck=1', grid lines are drawn.  The
             default value is `-0.2'.

       tmag: A number specifying the enlargement of text of the
             main title relative to the other annotating text
             of the plot.

        usr: A vector of the form `c(x1, x2, y1, y2)' giving
             the extremes of the user coordinates of the plot-
             ting region.

       xaxp: A vector of the form `c(x1, x2, n)' giving the
             coordinates of the extreme tick marks and the num-
             ber of intervals between tick-marks.

       xaxs: (Unimplemented) The style of axis interval calcu-
             lation to be used for the x-axis.

       xaxt: A character which specifies the axis type.  Speci-
             fying `"n"' causes an axis to be set up, but not
             plotted.

       xlog: A logical value. If `TRUE' a logarithmic scale is
             used.  The default is to use a linear scale.

        xpd: A logical value.  If `FALSE', all plotting is
             clipped to the plot region.

       yaxp: A vector of the form `c(y1, y2, n)' giving the
             coordinates of the extreme tick marks and the num-
             ber of intervals between tick-marks.

       yaxs: (Unimplemented) The style of axis interval calcu-
             lation to be used for the y-axis.

       yaxt: A character which specifies the axis type.  Speci-
             fying `"n"' causes an axis to be set up, but not
             plotted.

       ylog: A logical value. If `TRUE' a logarithmic scale is
             used.  The default is to use a linear scale.

   DDeessccrriippttiioonn::

        `par' can be used to set or query graphical parameters.
        Parameters can be set by specifying them as arguments
        to `par' in `tag = value' form, or by passing them as a
        list of tagged values.  In either case the previous
        values are returned in an invisible tagged list.  Such
        a list can be passed as an argument to `par' to restore
        the parameter values.

        Parameters are queried by giving vectors of character
        strings to `par'.  In this case, the values are
        returned in a tagged list.

   CCoolloorr SSppeecciiffiiccaattiioonn::

        Colors can be specified in several different ways.  The
        simplest way is with a character string giving the
        color name (e.g., `"red"').  A list of the possible
        colors can be obtained with the function `colors'.
        Alternatively, colors can be specified directly in
        terms of there RGB components with a string of the form
        `"#RRGGBB"' where each of the pairs `RR', `GG', `BB'
        consist of two hexidecimal digits giving a value in the
        range `00' to `FF'.  Colors can also be specified by
        giving an index into a small table of colors.  This
        provides compatibility with S.

        The functions `rgb', `hsv', `gray' and `rainbow' pro-
        vide additional ways of generating colors.

   LLiinnee TTyyppee SSppeecciiffiiccaattiioonn::

        Line types can either be specified by giving an index
        into a small built in table of line types (1=solid,
        2=dashed, 3=dotted) or directly as the lengths of
        on/off stretches of line.  This is done with a string
        of up to eight characters which give the lengths in
        consecutive positions in the string.  For example, the
        string `"33"' specifies three pixels on followed by
        three off and `"3313"' specifies three pixels on fol-
        lowed by three off followed by one on and finally three
        off.

   SSeeee AAllssoo::

        `colors', `gray', `rainbow', `rgb'; `options' for other
        setup parameters; graphic devices `x11', `postscript'.

   EExxaammpplleess::

        op <- par(mfrow = c(2, 2), # 2 x 2 pictures on one plot
                  pty = "s")      # square plotting region, independent of device size

        ## At end of plotting, reset to previous settings:
        par(op)

