prevR.colors: Continuous color palettes.

Description Usage Arguments Details Value Note See Also Examples

Description

Functions generating color palettes useable with R graphical functions, in particular with sp::spplot(). These palettes are continuous, contrast being accentuated by darkening and lightening extrem values. prevR.demo.pal plot the available palettes. prevR.colors.qgis.pal export a palette in a text file readable by Quantum GIS, an open-source mapping software.

Usage

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Arguments

n

number of different colors in the palette.

border

border color.

main

title.

file

file name with extension.

at

list of values of the palette.

pal

color palette to use ("red", "green", "blue" or "gray").

inverse

use the inverse palette?

Details

prevR.colors.red() produces a color gradation from white/yellow to red/dark red.
prevR.colors.blue() produces a color gradation from light blue to dark blue.
prevR.colors.green() produces a color gradation from light green to dark green.
prevR.colors.gray() produces a color gradation from white/light gray to dark gray/black.

Functions with a suffix .inverse produce the same color gradation, but from dark colors to light ones.

Value

prevR.demo.pal() plot the color palettes.

prevR.colors.qgis.pal() export a color palette in a text file readable by Quantum GIS.

The other functions return a list of colors coded in hexadecimal.

Note

To obtain the liste of colors in RGB (Red/Green/Blue), use the function grDevices::col2rgb(). The code of prevR.demo.pal() was adapted from the function demo.pal presented in the examples of grDevices::rainbow().

See Also

Other color palettes are available in R. See for example grDevices::rainbow() or the package RColorBrewer.

Examples

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prevR.demo.pal(25)
prevR.colors.red(5)
col2rgb(prevR.colors.red(5))

## Not run: 
 prevR.colors.qgis.pal('palette.txt', seq(0,25,length.out=100), 'red')

## End(Not run)

prevR documentation built on Aug. 28, 2020, 5:08 p.m.