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sp (version 2.1-2)

bpy.colors: blue-pink-yellow color scheme, which also prints well on black/white printers

Description

Create a vector of `n' ``contiguous'' colors.

Usage

bpy.colors(n = 100, cutoff.tails = 0.1, alpha = 1.0)

Value

A character vector, `cv', of color names. This can be used either to create a user-defined color palette for subsequent graphics by `palette(cv)', a `col=' specification in graphics functions or in `par'.

Arguments

n

number of colors (>= 1) to be in the palette

cutoff.tails

tail fraction to be cut off on each side. If 0, this palette runs from black to white; by cutting off the tails, it runs from blue to yellow, which looks nicer.

alpha

numeric; alpha transparency, 0 is fully transparent, 1 is opaque.

Author

unknown; the pallette was posted to gnuplot-info a few decades ago; R implementation Edzer Pebesma, edzer.pebesma@uni-muenster.de

See Also

Examples

Run this code
bpy.colors(10)
p <- expand.grid(x=1:30,y=1:30)
p$z <- p$x + p$y
coordinates(p) <- c("x", "y")
gridded(p) <- TRUE
image(p, col = bpy.colors(100), asp = 1)
# require(lattice)
# trellis.par.set("regions", list(col=bpy.colors())) # make this default pallette

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