This in primarily an internal openair function to make it easy for users to
select particular colour schemes, or define their own range of colours of a
user-defined length.Each of the pre-defined schemes have merits and their use will
depend on a particular situation. For showing incrementing
concentrations e.g. high concentrations emphasised, then
"default", "heat", "jet" and "increment" are very useful. See also
the description of RColorBrewer
schemes for the option
scheme
.
To colour-code categorical-type problems e.g. colours for different
pollutants, "hue" and "brewer1" are useful.
When publishing in black and white, "greyscale" is often convenient. With
most openair functions, as well as generating a greyscale colour gradient,
it also resets strip background and other coloured text and lines to
greyscale values.
Failing that, the user can define their own schemes based on R colour
names. To see the full list of names, type colors()
into R.