ocha palette with ramped colours

ocha_pal(palette = "blue", alpha = 1, reverse = FALSE)

Arguments

palette	Choose from 'ocha_palettes' list
alpha	transparency
reverse	If TRUE, the direction of the colours is reversed.

library(scales)
show_col(ocha_pal("blue")(7))

filled.contour(volcano, color.palette = ocha_pal(), asp = 1)