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Continuous scale constructor.

Source: R/scale-.r
continuous_scale.Rd

Continuous scale constructor.

Usage

continuous_scale(
  aesthetics,
  scale_name,
  palette,
  name = waiver(),
  breaks = waiver(),
  minor_breaks = waiver(),
  labels = waiver(),
  limits = NULL,
  rescaler = rescale,
  oob = censor,
  expand = waiver(),
  na.value = NA_real_,
  trans = "identity",
  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 axis or legend title. If NULL, the default, the name of the scale is taken from the first mapping used for that aesthetic.

breaks

One of:

  • NULL for no breaks

  • waiver() for the default breaks computed by the transformation object

  • A numeric vector of positions

  • A function that takes the limits as input and returns breaks as output

minor_breaks

One of:

  • NULL for no minor breaks

  • waiver() for the default breaks (one minor break between each major break)

  • A numeric vector of positions

  • A function that given the limits returns a vector of minor breaks.

labels

One of:

  • NULL for no labels

  • waiver() for the default labels computed by the transformation object

  • A character vector giving labels (must be same length as breaks)

  • A function that takes the breaks as input and returns labels as output

limits

A numeric vector of length two providing limits of the scale. Use NA to refer to the existing minimum or maximum.

rescaler

Used by diverging and n colour gradients (i.e. scale_colour_gradient2, scale_colour_gradientn). A function used to scale the input values to the range [0, 1].

oob

Function that handles limits outside of the scale limits (out of bounds). The default replaces out of bounds values with NA.

expand

A numeric vector of length two giving multiplicative and additive expansion constants. These constants ensure that the data is placed some distance away from the axes. The defaults are c(0.05, 0) for continuous variables, and c(0, 0.6) for discrete variables.

na.value

Missing values will be replaced with this value.

trans

Either the name of a transformation object, or the object itself. Built-in transformations include "asn", "atanh", "boxcox", "exp", "identity", "log", "log10", "log1p", "log2", "logit", "probability", "probit", "reciprocal", "reverse" and "sqrt".

A transformation object bundles together a transform, it's inverse, and methods for generating breaks and labels. Transformation objects are defined in the scales package, and are called name_trans, e.g. boxcox_trans. You can create your own transformation with trans_new.

guide

Name of guide object, or object itself.