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ggplot2 (version 2.0.0)

discrete_scale: Discrete scale constructor.

Description

Discrete scale constructor.

Usage

discrete_scale(aesthetics, scale_name, palette, name = waiver(),
  breaks = waiver(), labels = waiver(), limits = NULL,
  expand = waiver(), na.value = NA, drop = TRUE, guide = "legend")

Arguments

aesthetics
the names of the aesthetics that this scale works with
scale_name
the name of the scale
palette
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
name
the name of the scale - used as the axis label or the legend title
breaks
control the breaks in the guide. There are four possible types of input:
  • NULL: don't display any breaks
  • a character vector giving the breaks as they should appear on the axis or in the legend.
  • waiver()
labels
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.
limits
A character vector specifying the data range for the scale. and the default order of their display in guides.
expand
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 scale
na.value
how should missing values be displayed?
drop
drop unused factor levels from the scale (TRUE or FALSE)
guide
the name of, or actual function, used to create the guide. See guides for more info.