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ggplot2 (version 2.2.1)

scale_identity: 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 This will not produce a legend unless you also supply the breaks and labels.

Usage

scale_colour_identity(..., guide = "none")
scale_fill_identity(..., guide = "none")
scale_shape_identity(..., guide = "none")
scale_linetype_identity(..., guide = "none")
scale_alpha_identity(..., guide = "none")
scale_size_identity(..., guide = "none")

Arguments

...
Other arguments passed on to discrete_scale or continuous_scale
guide
Guide to use for this scale. Defaults to "none".

Examples

Run this code
ggplot(luv_colours, aes(u, v)) +
  geom_point(aes(colour = col), size = 3) +
  scale_color_identity() +
  coord_equal()

df <- data.frame(
  x = 1:4,
  y = 1:4,
  colour = c("red", "green", "blue", "yellow")
)
ggplot(df, aes(x, y)) + geom_tile(aes(fill = colour))
ggplot(df, aes(x, y)) +
  geom_tile(aes(fill = colour)) +
  scale_fill_identity()

# To get a legend guide, specify guide = "legend"
ggplot(df, aes(x, y)) +
  geom_tile(aes(fill = colour)) +
  scale_fill_identity(guide = "legend")
# But you'll typically also need to supply breaks and labels:
ggplot(df, aes(x, y)) +
  geom_tile(aes(fill = colour)) +
  scale_fill_identity("trt", labels = letters[1:4], breaks = df$colour,
  guide = "legend")

# cyl scaled to appropriate size
ggplot(mtcars, aes(mpg, wt)) +
  geom_point(aes(size = cyl))

# cyl used as point size
ggplot(mtcars, aes(mpg, wt)) +
  geom_point(aes(size = cyl)) +
  scale_size_identity()

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