Package 'ggshadow'

Connect Observations

Description

Plot a glow beneath the connected lines to make it easier to read a chart with several overlapping observations. geom_glowpath() connects the observations in the order in which they appear in the data. geom_glowline() connects them in order of the variable on the x axis. geom_glowstep() creates a stairstep plot, highlighting exactly when changes occur.

Usage

geom_glowpath(
  mapping = NULL,
  data = NULL,
  stat = "identity",
  position = "identity",
  ...,
  lineend = "butt",
  linejoin = "round",
  linemitre = 10,
  arrow = NULL,
  na.rm = FALSE,
  show.legend = NA,
  inherit.aes = TRUE
)

geom_glowline(
  mapping = NULL,
  data = NULL,
  stat = "identity",
  position = "identity",
  na.rm = FALSE,
  orientation = NA,
  show.legend = NA,
  inherit.aes = TRUE,
  ...
)

geom_glowstep(
  mapping = NULL,
  data = NULL,
  stat = "identity",
  position = "identity",
  direction = "hv",
  na.rm = FALSE,
  show.legend = NA,
  inherit.aes = TRUE,
  ...
)

Arguments

mapping	Set of aesthetic mappings created by aes() or aes_(). If specified and inherit.aes = TRUE (the default), it is combined with the default mapping at the top level of the plot. You must supply mapping if there is no plot mapping.
data	The data to be displayed in this layer. There are three options: If NULL, the default, the data is inherited from the plot data as specified in the call to ggplot(). A data.frame, or other object, will override the plot data. All objects will be fortified to produce a data frame. See fortify() for which variables will be created. A function will be called with a single argument, the plot data. The return value must be a data.frame, and will be used as the layer data. A function can be created from a formula (e.g. ~ head(.x, 10)).
stat	The statistical transformation to use on the data for this layer, as a string.
position	Position adjustment, either as a string, or the result of a call to a position adjustment function.
...	Other arguments passed on to layer(). These are often aesthetics, used to set an aesthetic to a fixed value, like colour = "red" or linewidth = 3. They may also be parameters to the paired geom/stat.
lineend	Line end style (round, butt, square).
linejoin	Line join style (round, mitre, bevel).
linemitre	Line mitre limit (number greater than 1).
arrow	Arrow specification, as created by grid::arrow().
na.rm	If FALSE, the default, missing values are removed with a warning. If TRUE, missing values are silently removed.
show.legend	logical. Should this layer be included in the legends? NA, the default, includes if any aesthetics are mapped. FALSE never includes, and TRUE always includes. It can also be a named logical vector to finely select the aesthetics to display.
inherit.aes	If FALSE, overrides the default aesthetics, rather than combining with them. This is most useful for helper functions that define both data and aesthetics and shouldn't inherit behaviour from the default plot specification, e.g. borders().
orientation	The orientation of the layer. The default (NA) automatically determines the orientation from the aesthetic mapping. In the rare event that this fails it can be given explicitly by setting orientation to either "x" or "y". See the Orientation section for more detail.
direction	direction of stairs: 'vh' for vertical then horizontal, 'hv' for horizontal then vertical, or 'mid' for step half-way between adjacent x-values.

Details

The group aesthetic determines which cases are connected together. These functions are designed as a straight replacement to the geom_path(), geom_line() and geom_step() functions. To set the order of drawing, make the colour aesthetic a factor, and set the order from bottom to top.

Value

a ggplot2 layer to add to a plot.

Functions

• geom_glowpath(): Connects observations in the order in which they appear in the data.

• geom_glowline(): Connects observations in order of the variable on the x axis.

• geom_glowstep(): Creates a stairstep plot, highlighting exactly when changes occur.

Missing value handling

geom_glowpath(), geom_glowline(), and geom_glowstep() handle NA as follows:

• If an NA occurs in the middle of a line, it breaks the line. No warning is shown, regardless of whether na.rm is TRUE or FALSE.

• If an NA occurs at the start or the end of the line and na.rm is FALSE (default), the NA is removed with a warning.

• If an NA occurs at the start or the end of the line and na.rm is TRUE, the NA is removed silently, without warning.

Aesthetics

Adds 3 new aesthetics to geom_path():

• shadowcolour defaults to path color, controls the color of the shadow.

• shadowlinewidth defaults to linewidth, controls the linewidth of the shadow.

• shadowalpha defaults to 0.06 * alpha or 0.06, controls the alpha of the glow.

See Also

ggplot2::geom_path(), ggplot2::geom_line(), ggplot2::geom_step(): Filled paths (polygons);

Examples

# geom_glowline() is suitable for time series
library(ggplot2)
ggplot(economics_long, aes(date, value01, colour = variable)) + geom_glowline()

---

Points

Description

The point geom is used to create scatterplots. geom_glowpoint() is designed as a drop in replacement for geom_point() with an added glow beneath the point to make a busy plot more aesthetically appealing or to make points stand out from the rest of the plot.

Usage

geom_glowpoint(
  mapping = NULL,
  data = NULL,
  stat = "identity",
  position = "identity",
  ...,
  na.rm = FALSE,
  show.legend = NA,
  inherit.aes = TRUE
)

Arguments

mapping	Set of aesthetic mappings created by aes() or aes_(). If specified and inherit.aes = TRUE (the default), it is combined with the default mapping at the top level of the plot. You must supply mapping if there is no plot mapping.
data	The data to be displayed in this layer. There are three options: If NULL, the default, the data is inherited from the plot data as specified in the call to ggplot(). A data.frame, or other object, will override the plot data. All objects will be fortified to produce a data frame. See fortify() for which variables will be created. A function will be called with a single argument, the plot data. The return value must be a data.frame, and will be used as the layer data. A function can be created from a formula (e.g. ~ head(.x, 10)).
stat	The statistical transformation to use on the data for this layer, as a string.
position	Position adjustment, either as a string, or the result of a call to a position adjustment function.
...	Other arguments passed on to layer(). These are often aesthetics, used to set an aesthetic to a fixed value, like colour = "red" or size = 3. They may also be parameters to the paired geom/stat.
na.rm	If FALSE, the default, missing values are removed with a warning. If TRUE, missing values are silently removed.
show.legend	logical. Should this layer be included in the legends? NA, the default, includes if any aesthetics are mapped. FALSE never includes, and TRUE always includes. It can also be a named logical vector to finely select the aesthetics to display.
inherit.aes	If FALSE, overrides the default aesthetics, rather than combining with them. This is most useful for helper functions that define both data and aesthetics and shouldn't inherit behaviour from the default plot specification, e.g. borders().

Value

a layer to add to a plot.

Aesthetics

Adds 3 new aesthetics to geom_point():

• shadowcolour defaults to the same color as the point, controls the color of the glow

• shadowsize defaults to size, controls the sie of the shadow.

• shadowalpha defaults to 0.06 * alpha or 0.06, controls the alpha of the glow

Examples

library( ggplot2 )
p <- ggplot(mtcars, aes(wt, mpg))
p + geom_shadowpoint()

---

Connect Observations

Description

Plot a shadow beneath the connected lines to make it easier to read a chart with several overlapping observations. geom_shadowpath() connects the observations in the order in which they appear in the data. geom_shadowline() connects them in order of the variable on the x axis. geom_shadowstep() creates a stairstep plot, highlighting exactly when changes occur.

Usage

geom_shadowpath(
  mapping = NULL,
  data = NULL,
  stat = "identity",
  position = "identity",
  ...,
  lineend = "butt",
  linejoin = "round",
  linemitre = 10,
  arrow = NULL,
  na.rm = FALSE,
  show.legend = NA,
  inherit.aes = TRUE
)

geom_shadowline(
  mapping = NULL,
  data = NULL,
  stat = "identity",
  position = "identity",
  na.rm = FALSE,
  orientation = NA,
  show.legend = NA,
  inherit.aes = TRUE,
  ...
)

geom_shadowstep(
  mapping = NULL,
  data = NULL,
  stat = "identity",
  position = "identity",
  direction = "hv",
  na.rm = FALSE,
  show.legend = NA,
  inherit.aes = TRUE,
  ...
)

Arguments

mapping	Set of aesthetic mappings created by aes() or aes_(). If specified and inherit.aes = TRUE (the default), it is combined with the default mapping at the top level of the plot. You must supply mapping if there is no plot mapping.
data	The data to be displayed in this layer. There are three options: If NULL, the default, the data is inherited from the plot data as specified in the call to ggplot(). A data.frame, or other object, will override the plot data. All objects will be fortified to produce a data frame. See fortify() for which variables will be created. A function will be called with a single argument, the plot data. The return value must be a data.frame, and will be used as the layer data. A function can be created from a formula (e.g. ~ head(.x, 10)).
stat	The statistical transformation to use on the data for this layer, as a string.
position	Position adjustment, either as a string, or the result of a call to a position adjustment function.
...	Other arguments passed on to layer(). These are often aesthetics, used to set an aesthetic to a fixed value, like colour = "red" or linewidth = 3. They may also be parameters to the paired geom/stat.
lineend	Line end style (round, butt, square).
linejoin	Line join style (round, mitre, bevel).
linemitre	Line mitre limit (number greater than 1).
arrow	Arrow specification, as created by grid::arrow().
na.rm	If FALSE, the default, missing values are removed with a warning. If TRUE, missing values are silently removed.
show.legend	logical. Should this layer be included in the legends? NA, the default, includes if any aesthetics are mapped. FALSE never includes, and TRUE always includes. It can also be a named logical vector to finely select the aesthetics to display.
inherit.aes	If FALSE, overrides the default aesthetics, rather than combining with them. This is most useful for helper functions that define both data and aesthetics and shouldn't inherit behaviour from the default plot specification, e.g. borders().
orientation	The orientation of the layer. The default (NA) automatically determines the orientation from the aesthetic mapping. In the rare event that this fails it can be given explicitly by setting orientation to either "x" or "y". See the Orientation section for more detail.
direction	direction of stairs: 'vh' for vertical then horizontal, 'hv' for horizontal then vertical, or 'mid' for step half-way between adjacent x-values.

Details

The group aesthetic determines which cases are connected together. These functions are designed as a straight replacement to the geom_path(), geom_line() and geom_step() functions. To set the order of drawing, make the colour aesthetic a factor, and set the order from bottom to top.

Value

a layer to add to a plot.

Functions

• geom_shadowpath(): Connects observations in the order in which they appear in the data.

• geom_shadowline(): Connects observations in order of the variable on the x axis.

• geom_shadowstep(): Creates a stairstep plot, highlighting exactly when changes occur.

Missing value handling

geom_shadowpath(), geom_shadowline(), and geom_shadowstep() handle NA as follows:

• If an NA occurs in the middle of a line, it breaks the line. No warning is shown, regardless of whether na.rm is TRUE or FALSE.

• If an NA occurs at the start or the end of the line and na.rm is FALSE (default), the NA is removed with a warning.

• If an NA occurs at the start or the end of the line and na.rm is TRUE, the NA is removed silently, without warning.

Aesthetics

Adds 3 new aesthetics to geom_path():

• shadowcolour defaults to white, controls the color of the shadow.

• shadowlinewidth defaults to 2.5 * linewidth, controls the linewidth of the shadow.

• shadowalpha defaults to 0.25 * alpha or 0.9, controls the alpha of the shadow.

See Also

ggplot2::geom_path(), ggplot2::geom_line(), ggplot2::geom_step(): Filled paths (polygons);

Examples

# geom_shadowline() is suitable for time series
library(ggplot2)
ggplot(economics_long, aes(date, value01, colour = variable)) + geom_shadowline()

ggplot(economics_long, aes(date, value01, colour = value01,
                           group = variable, alpha=date, shadowalpha=1)) +
          geom_shadowline()

---

Points

Description

The point geom is used to create scatterplots. geom_shadowpoint() is designed as a drop in replacement for geom_point() with an added shadow beneath the point to make a busy plot more aesthetically appealing or to make points stand out from the rest of the plot.

Usage

geom_shadowpoint(
  mapping = NULL,
  data = NULL,
  stat = "identity",
  position = "identity",
  ...,
  na.rm = FALSE,
  show.legend = NA,
  inherit.aes = TRUE
)

Arguments

mapping	Set of aesthetic mappings created by aes() or aes_(). If specified and inherit.aes = TRUE (the default), it is combined with the default mapping at the top level of the plot. You must supply mapping if there is no plot mapping.
data	The data to be displayed in this layer. There are three options: If NULL, the default, the data is inherited from the plot data as specified in the call to ggplot(). A data.frame, or other object, will override the plot data. All objects will be fortified to produce a data frame. See fortify() for which variables will be created. A function will be called with a single argument, the plot data. The return value must be a data.frame, and will be used as the layer data. A function can be created from a formula (e.g. ~ head(.x, 10)).
stat	The statistical transformation to use on the data for this layer, as a string.
position	Position adjustment, either as a string, or the result of a call to a position adjustment function.
...	Other arguments passed on to layer(). These are often aesthetics, used to set an aesthetic to a fixed value, like colour = "red" or size = 3. They may also be parameters to the paired geom/stat.
na.rm	If FALSE, the default, missing values are removed with a warning. If TRUE, missing values are silently removed.
show.legend	logical. Should this layer be included in the legends? NA, the default, includes if any aesthetics are mapped. FALSE never includes, and TRUE always includes. It can also be a named logical vector to finely select the aesthetics to display.
inherit.aes	If FALSE, overrides the default aesthetics, rather than combining with them. This is most useful for helper functions that define both data and aesthetics and shouldn't inherit behaviour from the default plot specification, e.g. borders().

Value

a layer to add to a plot.

Aesthetics

Adds 3 new aesthetics to geom_point():

• shadowcolour defaults to white, controls the color of the shadow.

• shadowsize defaults to 1.8 * size, controls the size of the shadow.

• shadowalpha defaults to 0.25 * alpha or 0.9, controls the alpha of the shadow.

Examples

library( ggplot2 )
p <- ggplot(mtcars, aes(wt, mpg))
p + geom_shadowpoint()

---

Sequential, diverging and qualitative colour scales from colorbrewer.org

Description

The brewer scales provides sequential, diverging and qualitative colour schemes from ColorBrewer. These are particularly well suited to display discrete values on a map. See https://colorbrewer2.org for more information.

Usage

scale_shadowcolour_brewer(
  ...,
  type = "seq",
  palette = 1,
  direction = 1,
  aesthetics = "shadowcolour"
)

scale_shadowcolour_distiller(
  ...,
  type = "seq",
  palette = 1,
  direction = -1,
  values = NULL,
  space = "Lab",
  na.value = "grey50",
  guide = "colourbar",
  aesthetics = "shadowcolour"
)

scale_shadowcolour_fermenter(
  ...,
  type = "seq",
  palette = 1,
  direction = -1,
  na.value = "grey50",
  guide = "coloursteps",
  aesthetics = "shadowcolour"
)

Arguments

...	Other arguments passed on to discrete_scale(), continuous_scale(), or binned_scale(), for brewer, distiller, and fermenter variants respectively, to control name, limits, breaks, labels and so forth.
type	One of "seq" (sequential), "div" (diverging) or "qual" (qualitative)
palette	If a string, will use that named palette. If a number, will index into the list of palettes of appropriate type. The list of available palettes can found in the Palettes section.
direction	Sets the order of colours in the scale. If 1, the default, colours are as output by RColorBrewer::brewer.pal(). If -1, the order of colours is reversed.
aesthetics	Character string or vector of character strings listing the name(s) of the aesthetic(s) that this scale works with. This can be useful, for example, to apply colour settings to the colour and fill aesthetics at the same time, via aesthetics = c("colour", "fill").
values	if colours should not be evenly positioned along the gradient this vector gives the position (between 0 and 1) for each colour in the colours vector. See rescale() for a convenience function to map an arbitrary range to between 0 and 1.
space	colour space in which to calculate gradient. Must be "Lab" - other values are deprecated.
na.value	Colour to use for missing values
guide	Type of legend. Use "colourbar" for continuous colour bar, or "legend" for discrete colour legend.

Details

The brewer scales were carefully designed and tested on discrete data. They were not designed to be extended to continuous data, but results often look good. Your mileage may vary.

Value

a scale object to add to a plot.

Palettes

The following palettes are available for use with these scales:

Diverging

BrBG, PiYG, PRGn, PuOr, RdBu, RdGy, RdYlBu, RdYlGn, Spectral

Qualitative

Accent, Dark2, Paired, Pastel1, Pastel2, Set1, Set2, Set3

Sequential

Blues, BuGn, BuPu, GnBu, Greens, Greys, Oranges, OrRd, PuBu, PuBuGn, PuRd, Purples, RdPu, Reds, YlGn, YlGnBu, YlOrBr, YlOrRd

Modify the palette through the palette argument.

Note

The distiller scales extend brewer to continuous scales by smoothly interpolating 7 colours from any palette to a continuous scale. The fermenter scales provide binned versions of the brewer scales.

See Also

Other colour scales: scale_colour_hue, scale_colour_steps, scale_gradient, scale_grey, scale_viridis

Examples

library( ggplot2 )
p <- ggplot(mtcars, aes(wt, mpg, shadowcolor=as.factor(gear)))
p + geom_shadowpoint() + scale_shadowcolour_brewer()

library( ggplot2 )
p <- ggplot(mtcars, aes(wt, mpg, shadowcolor=gear))
p + geom_shadowpoint() + scale_shadowcolour_distiller() + guides(shadowcolor='none')

library( ggplot2 )
p <- ggplot(mtcars, aes(wt, mpg, shadowcolor=as.factor(gear)))
p + geom_shadowpoint() + scale_shadowcolour_brewer()

---

Evenly spaced colours for discrete data

Description

This is the default colour scale for categorical variables. It maps each level to an evenly spaced hue on the colour wheel. It does not generate colour-blind safe palettes.

Usage

scale_shadowcolour_hue(
  ...,
  h = c(0, 360) + 15,
  c = 100,
  l = 65,
  h.start = 0,
  direction = 1,
  na.value = "grey50",
  aesthetics = "shadowcolour"
)

scale_shadowcolour_discrete(
  ...,
  h = c(0, 360) + 15,
  c = 100,
  l = 65,
  h.start = 0,
  direction = 1,
  na.value = "grey50",
  aesthetics = "shadowcolour"
)

Arguments

...	Arguments passed on to ggplot2::discrete_scale scale_name The name of the scale that should be used for error messages associated with this 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 (e.g., scales::pal_hue()). name The name of the scale. Used as the axis or legend title. If waiver(), the default, the name of the scale is taken from the first mapping used for that aesthetic. If NULL, the legend title will be omitted. breaks One of: NULL for no breaks waiver() for the default breaks (the scale limits) A character vector of breaks A function that takes the limits as input and returns breaks as output. Also accepts rlang lambda function notation. 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) An expression vector (must be the same length as breaks). See ?plotmath for details. A function that takes the breaks as input and returns labels as output. Also accepts rlang lambda function notation. limits One of: NULL to use the default scale values A character vector that defines possible values of the scale and their order A function that accepts the existing (automatic) values and returns new ones. Also accepts rlang lambda function notation. 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 expansion() to generate the values for the 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. na.translate 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 na.translate = FALSE. drop Should unused factor levels be omitted from the scale? The default, TRUE, uses the levels that appear in the data; FALSE uses all the levels in the factor. guide A function used to create a guide or its name. See guides() for more information. position For position scales, The position of the axis. left or right for y axes, top or bottom for x axes. super The super class to use for the constructed scale
h	range of hues to use, in [0, 360]
c	chroma (intensity of colour), maximum value varies depending on combination of hue and luminance.
l	luminance (lightness), in [0, 100]
h.start	hue to start at
direction	direction to travel around the colour wheel, 1 = clockwise, -1 = counter-clockwise
na.value	Colour to use for missing values
aesthetics	Character string or vector of character strings listing the name(s) of the aesthetic(s) that this scale works with. This can be useful, for example, to apply colour settings to the colour and fill aesthetics at the same time, via aesthetics = c("colour", "fill").

Value

a scale object to add to a plot.

See Also

Other colour scales: scale_brewer, scale_colour_steps, scale_gradient, scale_grey, scale_viridis

Examples

library( ggplot2 )
p <- ggplot(mtcars, aes(wt, mpg, shadowcolor=as.factor(gear)))
p + geom_shadowpoint() + scale_shadowcolour_hue()

library( ggplot2 )
p <- ggplot(mtcars, aes(wt, mpg, shadowcolor=as.factor(gear)))
p + geom_shadowpoint() + scale_shadowcolour_discrete()

---

Binned gradient colour scales

Description

⁠scale_*_steps⁠ creates a two colour binned gradient (low-high), ⁠scale_*_steps2⁠ creates a diverging binned colour gradient (low-mid-high), and ⁠scale_*_stepsn⁠ creates a n-colour binned gradient. These scales are binned variants of the gradient scale family and works in the same way.

Usage

scale_shadowcolour_steps(
  ...,
  low = "#132B43",
  high = "#56B1F7",
  space = "Lab",
  na.value = "grey50",
  guide = "coloursteps",
  aesthetics = "shadowcolour"
)

scale_shadowcolour_steps2(
  ...,
  low = muted("red"),
  mid = "white",
  high = muted("blue"),
  midpoint = 0,
  space = "Lab",
  na.value = "grey50",
  guide = "coloursteps",
  aesthetics = "shadowcolour"
)

scale_shadowcolour_stepsn(
  ...,
  colours,
  values = NULL,
  space = "Lab",
  na.value = "grey50",
  guide = "coloursteps",
  aesthetics = "shadowcolour",
  colors
)

Arguments

...	Arguments passed on to ggplot2::binned_scale name The name of the scale. Used as the axis or legend title. If waiver(), the default, the name of the scale is taken from the first mapping used for that aesthetic. If NULL, the legend title will be omitted. 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 (e.g., a function returned by scales::extended_breaks()). Also accepts rlang lambda function notation. 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) An expression vector (must be the same length as breaks). See ?plotmath for details. A function that takes the breaks as input and returns labels as output. Also accepts rlang lambda function notation. limits One of: NULL to use the default scale range A numeric vector of length two providing limits of the scale. Use NA to refer to the existing minimum or maximum A function that accepts the existing (automatic) limits and returns new limits. Also accepts rlang lambda function notation. Note that setting limits on positional scales will remove data outside of the limits. If the purpose is to zoom, use the limit argument in the coordinate system (see coord_cartesian()). oob One of: Function that handles limits outside of the scale limits (out of bounds). Also accepts rlang lambda function notation. The default (scales::censor()) replaces out of bounds values with NA. scales::squish() for squishing out of bounds values into range. scales::squish_infinite() for squishing infinite values into range. 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 expansion() to generate the values for the 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. n.breaks The number of break points to create if breaks are not given directly. nice.breaks Logical. Should breaks be attempted placed at nice values instead of exactly evenly spaced between the limits. If 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 explicitly. right Should the intervals be closed on the right (TRUE, default) or should the intervals be closed on the left (FALSE)? 'Closed on the right' means that values at break positions are part of the lower bin (open on the left), whereas they are part of the upper bin when intervals are closed on the left (open on the right). trans Deprecated in favour of transform. show.limits should the limits of the scale appear as ticks position For position scales, The position of the axis. left or right for y axes, top or bottom for x axes. super The super class to use for the constructed scale
low, high	Colours for low and high ends of the gradient.
space	colour space in which to calculate gradient. Must be "Lab" - other values are deprecated.
na.value	Colour to use for missing values
guide	Type of legend. Use "colourbar" for continuous colour bar, or "legend" for discrete colour legend.
aesthetics	Character string or vector of character strings listing the name(s) of the aesthetic(s) that this scale works with. This can be useful, for example, to apply colour settings to the colour and fill aesthetics at the same time, via aesthetics = c("colour", "fill").
mid	colour for mid point
midpoint	The midpoint (in data value) of the diverging scale. Defaults to 0.
colours, colors	Vector of colours to use for n-colour gradient.
values	if colours should not be evenly positioned along the gradient this vector gives the position (between 0 and 1) for each colour in the colours vector. See rescale() for a convenience function to map an arbitrary range to between 0 and 1.

Details

Default colours are generated with munsell and mnsl(c("2.5PB 2/4", "2.5PB 7/10")). Generally, for continuous colour scales you want to keep hue constant, but vary chroma and luminance. The munsell package makes this easy to do using the Munsell colour system.

Value

a scale object to add to a plot.

See Also

scales::seq_gradient_pal() for details on underlying palette

Other colour scales: scale_brewer, scale_colour_hue, scale_gradient, scale_grey, scale_viridis

Examples

library( ggplot2 )
p <- ggplot(mtcars, aes(wt, mpg, shadowcolor=gear))
p + geom_shadowpoint() + scale_shadowcolour_steps() + guides(shadowcolour='none')

library( ggplot2 )
p <- ggplot(mtcars, aes(wt, mpg, shadowcolor=gear))
p + geom_shadowpoint() + scale_shadowcolour_steps2() + guides(shadowcolour='none')

library( ggplot2 )
p <- ggplot(mtcars, aes(wt, mpg, shadowcolor=gear))
p <- p + geom_shadowpoint() + scale_shadowcolour_stepsn(colours=c('red', 'yellow'))
p + guides(shadowcolour='none')

---

Continuous and binned colour scales

Description

Colour scales for continuous data default to the values of the ggplot2.continuous.colour and ggplot2.continuous.fill options. These options() default to "gradient" (i.e., scale_colour_gradient() and scale_fill_gradient())

Usage

scale_shadowcolour_continuous(
  ...,
  type = getOption("ggplot2.continuous.colour", default = "gradient")
)

scale_shadowcolour_binned(
  ...,
  type = getOption("ggplot2.binned.colour", default =
    getOption("ggplot2.continuous.colour", default = "gradient"))
)

Arguments

...	Additional parameters passed on to the scale type
type	One of the following: "gradient" (the default) "viridis" A function that returns a continuous colour scale.

Value

a scale object to add to a plot.

Color Blindness

Many color palettes derived from RGB combinations (like the "rainbow" color palette) are not suitable to support all viewers, especially those with color vision deficiencies. Using viridis type, which is perceptually uniform in both colour and black-and-white display is an easy option to ensure good perceptive properties of your visulizations. The colorspace package offers functionalities

• to generate color palettes with good perceptive properties,

• to analyse a given color palette, like emulating color blindness,

• and to modify a given color palette for better perceptivity.

For more information on color vision deficiencies and suitable color choices see the paper on the colorspace package and references therein.

See Also

scale_colour_gradient(), scale_colour_viridis_c(), scale_colour_steps(), scale_colour_viridis_b(), scale_fill_gradient(), scale_fill_viridis_c(), scale_fill_steps(), and scale_fill_viridis_b()

Examples

library( ggplot2 )
p <- ggplot(mtcars, aes(wt, mpg, shadowcolor=gear))
p + geom_shadowpoint() + scale_shadowcolour_continuous() + guides(shadowcolour='none')


library( ggplot2 )
p <- ggplot(mtcars, aes(wt, mpg, shadowcolor=gear))
p + geom_shadowpoint() + scale_shadowcolour_binned() + guides(shadowcolour='none')

---

Gradient colour scales

Description

⁠scale_*_gradient⁠ creates a two colour gradient (low-high), ⁠scale_*_gradient2⁠ creates a diverging colour gradient (low-mid-high), ⁠scale_*_gradientn⁠ creates a n-colour gradient.

Usage

scale_shadowcolour_gradient(
  ...,
  low = "#132B43",
  high = "#56B1F7",
  space = "Lab",
  na.value = "grey50",
  guide = "colourbar",
  aesthetics = "shadowcolour"
)

scale_shadowcolour_gradient2(
  ...,
  low = muted("red"),
  mid = "white",
  high = muted("blue"),
  midpoint = 0,
  space = "Lab",
  na.value = "grey50",
  guide = "colourbar",
  aesthetics = "shadowcolour"
)

scale_shadowcolour_gradientn(
  ...,
  colours,
  values = NULL,
  space = "Lab",
  na.value = "grey50",
  guide = "colourbar",
  aesthetics = "shadowcolour",
  colors
)

scale_shadowcolour_datetime(
  ...,
  low = "#132B43",
  high = "#56B1F7",
  space = "Lab",
  na.value = "grey50",
  guide = "colourbar"
)

scale_shadowcolour_date(
  ...,
  low = "#132B43",
  high = "#56B1F7",
  space = "Lab",
  na.value = "grey50",
  guide = "colourbar"
)

Arguments

...	Arguments passed on to ggplot2::continuous_scale scale_name The name of the scale that should be used for error messages associated with this scale. palette A palette function that when called with a numeric vector with values between 0 and 1 returns the corresponding output values (e.g., scales::pal_area()). name The name of the scale. Used as the axis or legend title. If waiver(), the default, the name of the scale is taken from the first mapping used for that aesthetic. If NULL, the legend title will be omitted. 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 (e.g., a function returned by scales::extended_breaks()). Also accepts rlang lambda function notation. 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. Also accepts rlang lambda function notation. When the function has two arguments, it will be given the limits and major breaks. 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 breaks = waiver(). Use NULL to use the default number of breaks given by the transformation. 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) An expression vector (must be the same length as breaks). See ?plotmath for details. A function that takes the breaks as input and returns labels as output. Also accepts rlang lambda function notation. limits One of: NULL to use the default scale range A numeric vector of length two providing limits of the scale. Use NA to refer to the existing minimum or maximum A function that accepts the existing (automatic) limits and returns new limits. Also accepts rlang lambda function notation. Note that setting limits on positional scales will remove data outside of the limits. If the purpose is to zoom, use the limit argument in the coordinate system (see coord_cartesian()). rescaler A function used to scale the input values to the range [0, 1]. This is always scales::rescale(), except for diverging and n colour gradients (i.e., scale_colour_gradient2(), scale_colour_gradientn()). The rescaler is ignored by position scales, which always use scales::rescale(). Also accepts rlang lambda function notation. oob One of: Function that handles limits outside of the scale limits (out of bounds). Also accepts rlang lambda function notation. The default (scales::censor()) replaces out of bounds values with NA. scales::squish() for squishing out of bounds values into range. scales::squish_infinite() for squishing infinite values into range. 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 expansion() to generate the values for the 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. trans Deprecated in favour of transform. position For position scales, The position of the axis. left or right for y axes, top or bottom for x axes. super The super class to use for the constructed scale
low, high	Colours for low and high ends of the gradient.
space	colour space in which to calculate gradient. Must be "Lab" - other values are deprecated.
na.value	Colour to use for missing values
guide	Type of legend. Use "colourbar" for continuous colour bar, or "legend" for discrete colour legend.
aesthetics	Character string or vector of character strings listing the name(s) of the aesthetic(s) that this scale works with. This can be useful, for example, to apply colour settings to the colour and fill aesthetics at the same time, via aesthetics = c("colour", "fill").
mid	colour for mid point
midpoint	The midpoint (in data value) of the diverging scale. Defaults to 0.
colours, colors	Vector of colours to use for n-colour gradient.
values	if colours should not be evenly positioned along the gradient this vector gives the position (between 0 and 1) for each colour in the colours vector. See rescale() for a convenience function to map an arbitrary range to between 0 and 1.

Details

Default colours are generated with munsell and mnsl(c("2.5PB 2/4", "2.5PB 7/10")). Generally, for continuous colour scales you want to keep hue constant, but vary chroma and luminance. The munsell package makes this easy to do using the Munsell colour system.

Value

a scale object to add to a plot.

See Also

scales::seq_gradient_pal() for details on underlying palette

Other colour scales: scale_brewer, scale_colour_hue, scale_colour_steps, scale_grey, scale_viridis

Examples

library( ggplot2 )
p <- ggplot(economics, aes(date, unemploy, shadowcolor=pce))
p + geom_shadowline() + scale_shadowcolour_gradient() + guides(shadowcolour='none')

library( ggplot2 )
p <- ggplot(economics, aes(date, unemploy, shadowcolor=pce))
p + geom_shadowline() + scale_shadowcolour_gradient2() + guides(shadowcolour='none')

library( ggplot2 )
p <- ggplot(economics, aes(date, unemploy, shadowcolor=pce))
p <- p + geom_shadowline() + scale_shadowcolour_gradientn(colours=c('red', 'green'))
p + guides(shadowcolour='none')

library( ggplot2 )
p <- ggplot(economics, aes(uempmed, unemploy, shadowcolor=as.POSIXct(date)))
p + geom_shadowpath() + scale_shadowcolour_datetime() + guides(shadowcolour='none')

library( ggplot2 )
p <- ggplot(economics, aes(uempmed, unemploy, shadowcolor=date))
p + geom_shadowpath() + scale_shadowcolour_date() + guides(shadowcolour='none')

---

Sequential grey colour scales

Description

Based on gray.colors(). This is black and white equivalent of scale_colour_gradient().

Usage

scale_shadowcolour_grey(
  ...,
  start = 0.2,
  end = 0.8,
  na.value = "red",
  aesthetics = "shadowcolour"
)

Arguments

...	Arguments passed on to ggplot2::discrete_scale scale_name The name of the scale that should be used for error messages associated with this 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 (e.g., scales::pal_hue()). name The name of the scale. Used as the axis or legend title. If waiver(), the default, the name of the scale is taken from the first mapping used for that aesthetic. If NULL, the legend title will be omitted. breaks One of: NULL for no breaks waiver() for the default breaks (the scale limits) A character vector of breaks A function that takes the limits as input and returns breaks as output. Also accepts rlang lambda function notation. 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) An expression vector (must be the same length as breaks). See ?plotmath for details. A function that takes the breaks as input and returns labels as output. Also accepts rlang lambda function notation. limits One of: NULL to use the default scale values A character vector that defines possible values of the scale and their order A function that accepts the existing (automatic) values and returns new ones. Also accepts rlang lambda function notation. 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 expansion() to generate the values for the 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. na.translate 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 na.translate = FALSE. drop Should unused factor levels be omitted from the scale? The default, TRUE, uses the levels that appear in the data; FALSE uses all the levels in the factor. guide A function used to create a guide or its name. See guides() for more information. position For position scales, The position of the axis. left or right for y axes, top or bottom for x axes. super The super class to use for the constructed scale
start	grey value at low end of palette
end	grey value at high end of palette
na.value	Colour to use for missing values
aesthetics	Character string or vector of character strings listing the name(s) of the aesthetic(s) that this scale works with. This can be useful, for example, to apply colour settings to the colour and fill aesthetics at the same time, via aesthetics = c("colour", "fill").

Value

a scale object to add to a plot.

See Also

Other colour scales: scale_brewer, scale_colour_hue, scale_colour_steps, scale_gradient, scale_viridis

Examples

library( ggplot2 )
p <- ggplot(mtcars, aes(wt, mpg, shadowcolour=as.factor(gear)))
p + geom_glowpoint() + scale_shadowcolour_grey() + guides(shadowcolour='none')

---

Use values without scaling

Description

Use this set of scales when your data has already been scaled, i.e. it already represents aesthetic values that ggplot2 can handle directly. These scales will not produce a legend unless you also supply the breaks, labels, and type of guide you want.

Usage

scale_shadowcolour_identity(..., guide = "none", aesthetics = "shadowcolour")

Arguments

...	Other arguments passed on to discrete_scale() or continuous_scale()
guide	Guide to use for this scale. Defaults to "none".
aesthetics	Character string or vector of character strings listing the name(s) of the aesthetic(s) that this scale works with. This can be useful, for example, to apply colour settings to the colour and fill aesthetics at the same time, via aesthetics = c("colour", "fill").

Details

The functions ggplot2::scale_colour_identity(), ggplot2::scale_fill_identity(), ggplot2::scale_size_identity(), etc. work on the aesthetics specified in the scale name: colour, fill, size, etc. However, the functions scale_colour_identity() and scale_fill_identity() also have an optional aesthetics argument that can be used to define both colour and fill aesthetic mappings via a single function call. The functions scale_discrete_identity() and scale_continuous_identity() are generic scales that can work with any aesthetic or set of aesthetics provided via the aesthetics argument.

Value

a scale object to add to a plot.

Examples

library( ggplot2 )
p <- ggplot(mtcars, aes(wt, mpg, shadowcolor='red'))
p + geom_shadowpoint() + scale_shadowcolour_identity()

---

Create your own discrete scale

Description

These functions allow you to specify your own set of mappings from levels in the data to aesthetic values.

Usage

scale_shadowcolour_manual(
  ...,
  values,
  aesthetics = "shadowcolour",
  breaks = waiver()
)

Arguments

...	Arguments passed on to ggplot2::discrete_scale scale_name The name of the scale that should be used for error messages associated with this 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 (e.g., scales::pal_hue()). name The name of the scale. Used as the axis or legend title. If waiver(), the default, the name of the scale is taken from the first mapping used for that aesthetic. If NULL, the legend title will be omitted. 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) An expression vector (must be the same length as breaks). See ?plotmath for details. A function that takes the breaks as input and returns labels as output. Also accepts rlang lambda function notation. limits One of: NULL to use the default scale values A character vector that defines possible values of the scale and their order A function that accepts the existing (automatic) values and returns new ones. Also accepts rlang lambda function notation. na.translate 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 na.translate = FALSE. na.value If na.translate = TRUE, what aesthetic value should the missing values be displayed as? Does not apply to position scales where NA is always placed at the far right. drop Should unused factor levels be omitted from the scale? The default, TRUE, uses the levels that appear in the data; FALSE uses all the levels in the factor. guide A function used to create a guide or its name. See guides() for more information. super The super class to use for the constructed scale
values	a set of aesthetic values to map data values to. The values will be matched in order (usually alphabetical) with the limits of the scale, or with breaks if provided. If this is a named vector, then the values will be matched based on the names instead. Data values that don't match will be given na.value.
aesthetics	Character string or vector of character strings listing the name(s) of the aesthetic(s) that this scale works with. This can be useful, for example, to apply colour settings to the colour and fill aesthetics at the same time, via aesthetics = c("colour", "fill").
breaks	One of: NULL for no breaks waiver() for the default breaks (the scale limits) A character vector of breaks A function that takes the limits as input and returns breaks as output

Details

The functions scale_colour_manual(), scale_fill_manual(), scale_size_manual(), etc. work on the aesthetics specified in the scale name: colour, fill, size, etc. However, the functions scale_colour_manual() and scale_fill_manual() also have an optional aesthetics argument that can be used to define both colour and fill aesthetic mappings via a single function call (see examples). The function scale_discrete_manual() is a generic scale that can work with any aesthetic or set of aesthetics provided via the aesthetics argument.

Value

a scale object to add to a plot.

Color Blindness

Many color palettes derived from RGB combinations (like the "rainbow" color palette) are not suitable to support all viewers, especially those with color vision deficiencies. Using viridis type, which is perceptually uniform in both colour and black-and-white display is an easy option to ensure good perceptive properties of your visulizations. The colorspace package offers functionalities

• to generate color palettes with good perceptive properties,

• to analyse a given color palette, like emulating color blindness,

• and to modify a given color palette for better perceptivity.

For more information on color vision deficiencies and suitable color choices see the paper on the colorspace package and references therein.

Examples

library( ggplot2 )
p <- ggplot(mtcars, aes(wt, mpg, shadowcolour=as.factor(gear)))
p <- p + geom_glowpoint() + guides(shadowcolour='none')
p + scale_shadowcolour_manual(values=c('red', 'blue', 'green'))

---

Viridis colour scales from viridisLite

Description

The viridis scales provide colour maps that are perceptually uniform in both colour and black-and-white. They are also designed to be perceived by viewers with common forms of colour blindness. See also https://bids.github.io/colormap/.

Usage

scale_shadowcolour_viridis_d(
  ...,
  alpha = 1,
  begin = 0,
  end = 1,
  direction = 1,
  option = "D",
  aesthetics = "shadowcolour"
)

scale_shadowcolour_viridis_c(
  ...,
  alpha = 1,
  begin = 0,
  end = 1,
  direction = 1,
  option = "D",
  values = NULL,
  space = "Lab",
  na.value = "grey50",
  guide = "colourbar",
  aesthetics = "shadowcolour"
)

scale_shadowcolour_viridis_b(
  ...,
  alpha = 1,
  begin = 0,
  end = 1,
  direction = 1,
  option = "D",
  values = NULL,
  space = "Lab",
  na.value = "grey50",
  guide = "coloursteps",
  aesthetics = "shadowcolour"
)

scale_shadowcolour_ordinal(
  ...,
  alpha = 1,
  begin = 0,
  end = 1,
  direction = 1,
  option = "D",
  aesthetics = "shadowcolour"
)

Arguments

...	Other arguments passed on to discrete_scale(), continuous_scale(), or binned_scale to control name, limits, breaks, labels and so forth.
alpha	The alpha transparency, a number in [0,1], see argument alpha in hsv.
begin, end	The (corrected) hue in ⁠[0,1]⁠ at which the color map begins and ends.
direction	Sets the order of colors in the scale. If 1, the default, colors are ordered from darkest to lightest. If -1, the order of colors is reversed.
option	A character string indicating the color map option to use. Eight options are available: "magma" (or "A") "inferno" (or "B") "plasma" (or "C") "viridis" (or "D") "cividis" (or "E") "rocket" (or "F") "mako" (or "G") "turbo" (or "H")
aesthetics	Character string or vector of character strings listing the name(s) of the aesthetic(s) that this scale works with. This can be useful, for example, to apply colour settings to the colour and fill aesthetics at the same time, via aesthetics = c("colour", "fill").
values	if colours should not be evenly positioned along the gradient this vector gives the position (between 0 and 1) for each colour in the colours vector. See rescale() for a convenience function to map an arbitrary range to between 0 and 1.
space	colour space in which to calculate gradient. Must be "Lab" - other values are deprecated.
na.value	Missing values will be replaced with this value.
guide	A function used to create a guide or its name. See guides() for more information.

Value

a scale object to add to a plot.

See Also

Other colour scales: scale_brewer, scale_colour_hue, scale_colour_steps, scale_gradient, scale_grey

Examples

library( ggplot2 )
p <- ggplot(mtcars, aes(wt, mpg, shadowcolour=as.factor(gear)))
p + geom_glowpoint() + scale_shadowcolour_viridis_d() + guides(shadowcolour='none')

library( ggplot2 )
p <- ggplot(mtcars, aes(wt, mpg, shadowcolour=gear))
p + geom_glowpoint() + scale_shadowcolour_viridis_c() + guides(shadowcolour='none')

library( ggplot2 )
p <- ggplot(mtcars, aes(wt, mpg, shadowcolour=gear))
p + geom_glowpoint() + scale_shadowcolour_viridis_b() + guides(shadowcolour='none')

library( ggplot2 )
p <- ggplot(mtcars, aes(wt, mpg, shadowcolour=as.factor(gear)))
p + geom_glowpoint() + scale_shadowcolour_ordinal() + guides(shadowcolour='none')

---