chl_pal {palr} | R Documentation |
Ocean colour colours for chlorophyll-a.
Description
Ocean colour palette for chlorophyll-a.
Usage
chl_pal(x, palette = FALSE, alpha = 1)
chlPal(x, palette = FALSE, alpha = 1, ...)
Arguments
x |
a vector of data values or a single number |
palette |
logical, if |
alpha |
value in 0,1 to specify opacity |
... |
currently unused |
Details
Flexible control of the chlorophyll-a palette. If x
is a
single number, the function returns that many colours evenly
spaced from the palette. If x
is a vector of multiple
values the palette is queried for colours matching those values,
and these are returned. If x
is missing and palette
is FALSE
then a function is returned that will generate n
evenly spaced colours from the palette, as per
colorRampPalette
.
Value
colours, palette, or function, see Details
References
Derived from a file once found at 'http://oceancolor.gsfc.nasa.gov/DOCS/palette_chl_etc.txt'
Examples
## Not run:
chl <- raadtools::readchla(xylim = c(100, 110, -50, -40))
## just get a small number of evenly space colours
plot(chl, col = chl_pal(10))
## store the full palette and work with values and colours
pal <- chl_pal()
## the standard full palette
plot(chl, breaks = pal$breaks, col = pal$cols)
## a custom set of values with matching colours
plot(chl, col = chl_pal(pal$breaks[seq(1, length(pal$breaks), length = 10)]))
## any number of colours stored as a function
myfun <- chl_pal()
plot(chl, col = myfun(18))
## just n colours
plot(chl, col = chl_pal(18))
## End(Not run)
[Package palr version 0.4.0 Index]