scale_gradientn {ggplot2}R Documentation

scale_gradientn

Description

Smooth gradient between n colours

Usage

scale_colour_gradientn(name=NULL, colours, values=NULL, rescale=TRUE, space="rgb", breaks=NULL, labels=NULL, limits=NULL, trans="identity", alpha=1, ...)
scale_fill_gradientn(name=NULL, colours, values=NULL, rescale=TRUE, space="rgb", breaks=NULL, labels=NULL, limits=NULL, trans="identity", alpha=1, ...)

Arguments

name name of scale to appear in legend or on axis. Maybe be an expression: see ?plotmath
colours NULL
values NULL
rescale NULL
space colour space to interpolate through, rgb or Lab, see ?colorRamp for details
breaks numeric vector indicating where breaks should lie
labels character vector giving labels associated with breaks
limits numeric vector of length 2, giving the extent of the scale
trans a transformer to use
alpha alpha value to use for colours
... other arguments

Details

This page describes scale_gradientn, see layer and qplot for how to create a complete plot from individual components.

Value

A layer

Author(s)

Hadley Wickham, http://had.co.nz/

See Also

Examples

## Not run: 
# scale_colour_gradient make it easy to use existing colour palettes

dsub <- subset(diamonds, x > 5 & x < 6 & y > 5 & y < 6)
dsub$diff <- with(dsub, sqrt(abs(x-y))* sign(x-y))
(d <- qplot(x, y, data=dsub, colour=diff))

d + scale_colour_gradientn(colour = rainbow(7))
d + scale_colour_gradientn(colour = topo.colors(10))
d + scale_colour_gradientn(colour = terrain.colors(10))

# You can force them to be symmetric by supplying a vector of 
# values, and turning rescaling off
max_val <- max(abs(dsub$diff))
values <- seq(-max_val, max_val, length = 11)

d + scale_colour_gradientn(colours = topo.colors(10), 
  values = values, rescale = FALSE)
d + scale_colour_gradientn(colours = terrain.colors(10), 
  values = values, rescale = FALSE)

## End(Not run)

[Package ggplot2 version 0.8.2 Index]