Should colors span possible range more extremely?
If TRUE, it has very light yellow and very dark blue values included,
using the result from RColorBrewer::brewer.pal(9, "YlGnBu"). DEFAULT: FALSE
yb
Should colors be in yellow-blue instead of the internal (nice) default? DEFAULT: FALSE
yr
Should colors be in yellow-red instead of the default? DEFAULT: FALSE
gb
Should colors be in green-blue instead of the default? DEFAULT: FALSE
colors
If not NULL, a color vector used in colorRampPalette. DEFAULT: NULL