Some palettes with dark colors at one end of the palette hide the
shape of the volcano in the dark colors. Viridis is bad.
Usage
pal.volcano(pal, n = 100, main = "")
Arguments
- pal
A palette function or a vector of colors.
- n
The number of colors to display for palette functions.
- main
Main title
Details
What to look for:
1. Can you locate the highest point on the volcano?
2. Are the upper-right and lower-right corners the same elevation?
3. Do any Mach bands circle the peak?
Examples
pal.volcano(parula)
pal.volcano(brewer.rdbu) # Mach banding is bad
pal.volcano(warmcool, main="warmcool") # No Mach band
pal.volcano(rev(viridis(100))) # Bad: peak position is hidden
