% Generated by roxygen2: do not edit by hand
% Please edit documentation in R/scale-size.r
\name{scale_size}
\alias{scale_size}
\alias{scale_size_continuous}
\alias{scale_radius}
\alias{scale_size_binned}
\alias{scale_size_discrete}
\alias{scale_size_ordinal}
\alias{scale_size_area}
\alias{scale_size_binned_area}
\alias{scale_size_datetime}
\alias{scale_size_date}
\title{Scales for area or radius}
\usage{
scale_size(
  name = waiver(),
  breaks = waiver(),
  labels = waiver(),
  limits = NULL,
  range = c(1, 6),
  trans = "identity",
  guide = "legend"
)

scale_radius(
  name = waiver(),
  breaks = waiver(),
  labels = waiver(),
  limits = NULL,
  range = c(1, 6),
  trans = "identity",
  guide = "legend"
)

scale_size_binned(
  name = waiver(),
  breaks = waiver(),
  labels = waiver(),
  limits = NULL,
  range = c(1, 6),
  n.breaks = NULL,
  nice.breaks = TRUE,
  trans = "identity",
  guide = "bins"
)

scale_size_area(..., max_size = 6)

scale_size_binned_area(..., max_size = 6)
}
\arguments{
\item{name}{The name of the scale. Used as the axis or legend title. If
\code{waiver()}, the default, the name of the scale is taken from the first
mapping used for that aesthetic. If \code{NULL}, the legend title will be
omitted.}

\item{breaks}{One of:
\itemize{
\item \code{NULL} for no breaks
\item \code{waiver()} for the default breaks computed by the
\link[scales:trans_new]{transformation object}
\item A numeric vector of positions
\item A function that takes the limits as input and returns breaks
as output (e.g., a function returned by \code{\link[scales:breaks_extended]{scales::extended_breaks()}})
}}

\item{labels}{One of:
\itemize{
\item \code{NULL} for no labels
\item \code{waiver()} for the default labels computed by the
transformation object
\item A character vector giving labels (must be same length as \code{breaks})
\item A function that takes the breaks as input and returns labels
as output
}}

\item{limits}{One of:
\itemize{
\item \code{NULL} to use the default scale range
\item A numeric vector of length two providing limits of the scale.
Use \code{NA} to refer to the existing minimum or maximum
\item A function that accepts the existing (automatic) limits and returns
new limits
Note that setting limits on positional scales will \strong{remove} data outside of the limits.
If the purpose is to zoom, use the limit argument in the coordinate system
(see \code{\link[=coord_cartesian]{coord_cartesian()}}).
}}

\item{range}{a numeric vector of length 2 that specifies the minimum and
maximum size of the plotting symbol after transformation.}

\item{trans}{For continuous scales, the name of a transformation object
or the object itself. Built-in transformations include "asn", "atanh",
"boxcox", "date", "exp", "hms", "identity", "log", "log10", "log1p", "log2",
"logit", "modulus", "probability", "probit", "pseudo_log", "reciprocal",
"reverse", "sqrt" and "time".

A transformation object bundles together a transform, its inverse,
and methods for generating breaks and labels. Transformation objects
are defined in the scales package, and are called \verb{<name>_trans} (e.g.,
\code{\link[scales:boxcox_trans]{scales::boxcox_trans()}}). You can create your own
transformation with \code{\link[scales:trans_new]{scales::trans_new()}}.}

\item{guide}{A function used to create a guide or its name. See
\code{\link[=guides]{guides()}} for more information.}

\item{n.breaks}{An integer guiding the number of major breaks. The algorithm
may choose a slightly different number to ensure nice break labels. Will
only have an effect if \code{breaks = waiver()}. Use \code{NULL} to use the default
number of breaks given by the transformation.}

\item{nice.breaks}{Logical. Should breaks be attempted placed at nice values
instead of exactly evenly spaced between the limits. If \code{TRUE} (default)
the scale will ask the transformation object to create breaks, and this
may result in a different number of breaks than requested. Ignored if
breaks are given explicetly.}

\item{...}{
  Arguments passed on to \code{\link[=continuous_scale]{continuous_scale}}
  \describe{
    \item{\code{minor_breaks}}{One of:
\itemize{
\item \code{NULL} for no minor breaks
\item \code{waiver()} for the default breaks (one minor break between
each major break)
\item A numeric vector of positions
\item A function that given the limits returns a vector of minor breaks.
}}
    \item{\code{oob}}{One of:
\itemize{
\item Function that handles limits outside of the scale limits
(out of bounds).
\item The default (\code{\link[scales:oob]{scales::censor()}}) replaces out of
bounds values with \code{NA}.
\item \code{\link[scales:oob]{scales::squish()}} for squishing out of bounds values into range.
\item \code{\link[scales:oob]{scales::squish_infinite()}} for squishing infinite values into range.
}}
    \item{\code{na.value}}{Missing values will be replaced with this value.}
    \item{\code{expand}}{For position scales, a vector of range expansion constants used to add some
padding around the data to ensure that they are placed some distance
away from the axes. Use the convenience function \code{\link[=expansion]{expansion()}}
to generate the values for the \code{expand} argument. The defaults are to
expand the scale by 5\% on each side for continuous variables, and by
0.6 units on each side for discrete variables.}
    \item{\code{position}}{For position scales, The position of the axis.
\code{left} or \code{right} for y axes, \code{top} or \code{bottom} for x axes.}
    \item{\code{super}}{The super class to use for the constructed scale}
  }}

\item{max_size}{Size of largest points.}
}
\description{
\code{scale_size()} scales area, \code{scale_radius()} scales radius. The size
aesthetic is most commonly used for points and text, and humans perceive
the area of points (not their radius), so this provides for optimal
perception. \code{scale_size_area()} ensures that a value of 0 is mapped
to a size of 0. \code{scale_size_binned()} is a binned version of \code{scale_size()} that
scales by area (but does not ensure 0 equals an area of zero). For a binned
equivalent of \code{scale_size_area()} use \code{scale_size_binned_area()}.
}
\examples{
p <- ggplot(mpg, aes(displ, hwy, size = hwy)) +
   geom_point()
p
p + scale_size("Highway mpg")
p + scale_size(range = c(0, 10))

# If you want zero value to have zero size, use scale_size_area:
p + scale_size_area()

# Binning can sometimes make it easier to match the scaled data to the legend
p + scale_size_binned()

# This is most useful when size is a count
ggplot(mpg, aes(class, cyl)) +
  geom_count() +
  scale_size_area()

# If you want to map size to radius (usually bad idea), use scale_radius
p + scale_radius()
}
\seealso{
\code{\link[=scale_size_area]{scale_size_area()}} if you want 0 values to be mapped
to points with size 0.
}
