discrete_scale(aesthetics, scale_name, palette, name = waiver(), breaks = waiver(), labels = waiver(), limits = NULL, expand = waiver(), na.value = NA, drop = TRUE, guide = "legend")
- the names of the aesthetics that this scale works with
- the name of the scale
- a palette function that when called with a single integer
argument (the number of levels in the scale) returns the values that
they should take
- the name of the scale - used as the axis label or the legend
- control the breaks in the guide. There are four possible
types of input:
This parameter does not affect in any way how the data is scaled - it
only affects the appearance of the legend.
NULL: don't display any breaks
- a character vector giving the breaks as they should appear on the
axis or in the legend.
waiver() to use the default break computation.
- a function, that when called with a single argument, a character
vector giving the limits of the scale, returns a character vector
specifying which breaks to display.
NULL for no labels,
waiver() for default
labels (labels the same as breaks), a character vector the same length
as breaks, or a named character vector whose names are used to match
replacement the labels for matching breaks.
- A character vector specifying the data range for the scale.
and the default order of their display in guides.
- a numeric vector of length two, giving a multiplicative and
additive constant used to expand the range of the scales so that there
is a small gap between the data and the axes. The defaults are (0,0.6)
for discrete scales and (0.05,0) for continuous scales.
- how should missing values be displayed?
- Should unused factor levels be omitted from the scale?
TRUE, uses the levels that appear in the data;
FALSE uses all the levels in the factor.
- the name of, or actual function, used to create the
guides for more info.
Discrete scale constructor.