barwidthA numeric or a grid::unit() object specifying
the width of the colourbar. Default value is legend.key.width or
legend.key.size in theme() or theme.
barheightA numeric or a grid::unit() object specifying
the height of the colourbar. Default value is legend.key.height or
legend.key.size in theme() or theme.
frame.colourA string specifying the colour of the frame
drawn around the bar. If NULL (the default), no frame is drawn.
frame.linewidthA numeric specifying the width of the frame
drawn around the bar.
frame.linetypeA numeric specifying the linetype of the frame
drawn around the bar.
ticks.colourA string specifying the colour of the tick marks.
ticks.linewidthA numeric specifying the width of the tick marks.
draw.ulimA logical specifying if the upper limit tick marks should
be visible.
draw.llimA logical specifying if the lower limit tick marks should
be visible.
directionA character string indicating the direction of the guide.
One of "horizontal" or "vertical."
default.unitA character string indicating grid::unit()
for barwidth and barheight.
reverselogical. If TRUE the colourbar is reversed. By default,
the highest value is on the top and the lowest value is on the bottom
titleA character string or expression indicating a title of guide.
If NULL, the title is not shown. By default
(waiver()), the name of the scale object or the name
specified in labs() is used for the title.
title.positionA character string indicating the position of a
title. One of "top" (default for a vertical guide), "bottom", "left"
(default for a horizontal guide), or "right."
title.themeA theme object for rendering the title text. Usually the
object of element_text() is expected. By default, the theme is
specified by legend.title in theme() or theme.
title.hjustA number specifying horizontal justification of the
title text.
title.vjustA number specifying vertical justification of the title
text.
labellogical. If TRUE then the labels are drawn. If
FALSE then the labels are invisible.
label.positionA character string indicating the position of a
label. One of "top", "bottom" (default for horizontal guide), "left", or
"right" (default for vertical guide).
label.themeA theme object for rendering the label text. Usually the
object of element_text() is expected. By default, the theme is
specified by legend.text in theme().
label.hjustA numeric specifying horizontal justification of the
label text.
label.vjustA numeric specifying vertical justification of the label
text.
orderpositive integer less than 99 that specifies the order of
this guide among multiple guides. This controls the order in which
multiple guides are displayed, not the contents of the guide itself.
If 0 (default), the order is determined by a secret algorithm.