Selects colors from one of several palettes and output as a vector

This script draws upon a number of specified color libraries to extract a vector of colors for plotting, where the script that follows has a color parameter expecting a vector of colors.

Usage

gl.select.colors(
  x = NULL,
  library = NULL,
  palette = NULL,
  ncolors = NULL,
  select = NULL,
  verbose = NULL
)

Arguments

x: Optionally, provide a gl object from which to determine the number of populations [default NULL].
library: Name of the color library to be used [default scales::hue_pl].
palette: Name of the color palette to be pulled from the specified library [default is library specific] .
ncolors: number of colors to be displayed and returned [default 9].
select: select the colors to retain in the output vector [default NULL].
verbose: -- verbosity: 0, silent or fatal errors; 1, begin and end; 2, progress log; 3, progress and results summary; 5, full report [default 2 or as specified using gl.set.verbosity].

Value

A vector with the required number of colors

Details

The available color libraries and their palettes include:

library 'brewer' and the palettes available can be listed by RColorBrewer::display.brewer.all() and RColorBrewer::brewer.pal.info.
library 'gr.palette' and the palettes available can be listed by grDevices::palette.pals()
library 'r.hcl' and the palettes available can be listed by grDevices::hcl.pals()
library 'baseR' and the palettes available are: 'rainbow','heat', 'topo.colors','terrain.colors','cm.colors'.

If the nominated palette is not specified, all the palettes will be listed a nd a default palette will then be chosen.

The color palette will be displayed in the graphics window for the requested number of colors (or 9 if not specified),and the vector of colors returned for later use.

The select parameter can be used to select colors from the specified ncolors. For example, select=c(1,1,3) will select color 1, 1 again and 3 to retain in the final vector. This can be useful for fine-tuning color selection, and matching colors and shapes.

Author

Custodian: Arthur Georges -- Post to https://groups.google.com/d/forum/dartr

Examples

# SET UP DATASET
gl <- testset.gl
levels(pop(gl))<-c(rep('Coast',5),rep('Cooper',3),rep('Coast',5),
rep('MDB',8),rep('Coast',7),'Em.subglobosa','Em.victoriae')
# EXAMPLES -- SIMPLE
colors <- gl.select.colors()
#> Starting gl.select.colors 
#>   Warning: Number of required colors not specified, set to 9 to display the colors
#>   Warning: No color library or palette specified, set to default
#>     Select one of baseR, brewer, gr.palette or gr.hcl
#>   Library: scale
#>   Palette: hue_pal
#>   Showing and returning 9 colors for library scales : palette hue_pal 

#> Completed: gl.select.colors 
#> 
colors <- gl.select.colors(library='brewer',palette='Spectral',ncolors=6)
#> Starting gl.select.colors 
#>   Library: RColorBrewer
#>   Palette: brewer.pal
#>   Showing and returning 6 colors for library RColorBrewer : palette Spectral 

#> Completed: gl.select.colors 
#> 
colors <- gl.select.colors(library='baseR',palette='terrain.colors',ncolors=6)
#> Starting gl.select.colors 
#>   Library: baseR
#>   Palette: terrain.colors
#>   Showing and returning 6 colors for library baseR : palette terrain.colors 

#> Completed: gl.select.colors 
#> 
colors <- gl.select.colors(library='baseR',palette='rainbow',ncolors=12)
#> Starting gl.select.colors 
#>   Library: baseR
#>   Palette: rainbow
#>   Showing and returning 12 colors for library baseR : palette rainbow 

#> Completed: gl.select.colors 
#> 
colors <- gl.select.colors(library='gr.hcl',palette='RdBu',ncolors=12)
#> Starting gl.select.colors 
#>   Library: grDevices
#>   Palette: hcl.pals
#>   Showing and returning 12 colors for library grDevice-hcl : palette RdBu 

#> Completed: gl.select.colors 
#> 
colors <- gl.select.colors(library='gr.palette',palette='Pastel 1',ncolors=6)
#> Starting gl.select.colors 
#>   Library: grDevices
#>   Palette: palette.pals
#>   Showing and returning 6 colors for library grDevice-palette : palette Pastel 1 

#> Completed: gl.select.colors 
#> 
# EXAMPLES -- SELECTING colorS
colors <- gl.select.colors(library='baseR',palette='rainbow',ncolors=12,select=c(1,1,1,5,8))
#> Starting gl.select.colors 
#>   Library: baseR
#>   Palette: rainbow
#>   Showing and returning 5 of 12 colors for library baseR : palette rainbow 

#> Completed: gl.select.colors 
#> 
# EXAMPLES -- CROSS-CHECKING WITH A GENLIGHT OBJECT
colors <- gl.select.colors(x=gl,library='baseR',palette='rainbow',ncolors=12,select=c(1,1,1,5,8))
#> Starting gl.select.colors 
#>   Processing genlight object with SNP data
#>   Number of specified colors 5 corresponds to number of populations in supplied genlight object
#>   Library: baseR
#>   Palette: rainbow
#>   Showing and returning 5 of 12 colors for library baseR : palette rainbow 
#> Completed: gl.select.colors 
#>