Discrete scale constructor.
discrete_scale(aesthetics, scale_name, palette, name = waiver(), breaks = waiver(), labels = waiver(), limits = NULL, expand = waiver(), na.translate = TRUE, na.value = NA, drop = TRUE, guide = "legend", position = "left", super = ScaleDiscrete)
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 title
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.
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.
Unlike continuous scales, discrete scales can easily show
missing values, and do so by default. If you want to remove missing values
from a discrete scale, specify
Should unused factor levels be omitted from the scale?
the name of, or actual function, used to create the
The position of the axis. "left" or "right" for vertical scales, "top" or "bottom" for horizontal scales
The super class to use for the constructed scale