Bathymetry

Description

Deep bathymetry colours.

Usage

bathy_deep_pal(x, palette = FALSE, alpha = 1, ...)

bathyDeepPal(x, palette = FALSE, alpha = 1, ...)

Arguments

Details

Colour ramp suitable for deep waters (-5500) to sea level. The palette functions operate in 3 modes: 1) n colours - Pal(6) - returns 6 colours from the palette 2) data - Pal(c(10, 50, 100)) - return colours for 3 ice concentrations 3) palette - Pal(palette = TRUE) - return the full palette and breaks Derived from maps created in Matlab by Emmanuel Laurenceau.

Value

colours, palette, or function, see Details

Examples

plot(1:15, pch = 19, cex = 4, col  = bathy_deep_pal(15))

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

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)

Colour to hex conversion.

Description

Create colours from colour names in one easy step.

Usage

col2hex(x, alpha = 1)

Arguments

Value

character string of hex colours

Examples

col2hex(c("aliceblue", "firebrick"), alpha = c(1, .5))
col2hex(c("#FFFFFF", "#123456FF"), alpha = 0.1)

Colours for data values

Description

Scales input data to the palette, so that colour is mapped linearly to the range of values.

Usage

d_pal(x, pal = hcl.colors(84))

data_pal(x, pal = hcl.colors(84))

Arguments

Details

Default palette 'pal' is the 'viridis' colours of [grDevices::hcl.colors()], and may be literal colour values or a function.

[data_pal()] is an alias of [d_pal()].

Examples

plot(1:100, col = d_pal(1:100))
plot(1:100, col = d_pal(1:100, chl_pal))

Sea ice colours

Description

Colours for sea ice.

Usage

ice_pal(x, palette = FALSE, alpha = 1, ..., amsre = FALSE)

icePal(x, palette = FALSE, alpha = 1, ...)

Arguments

Details

The palette functions operate in 3 modes: 1) n colours - Pal(6) - returns 6 colours from the palette 2) data - Pal(c(10, 50, 100)) - return colours for 3 ice concentrations 3) palette - Pal(palette = TRUE) - return the full palette and breaks

Value

colours, palette, or function, see Details

References

amsre colours derived from http://www.iup.uni-bremen.de/seaice/amsr/., nsidc colours extracted in data-raw/.

Examples

## Not run: 
library(raster)
r <- raster(system.file("extdata", "nt_20140320_f17_v01_s.bin", package = "graticule") )
icp <- ice_pal(palette = TRUE)
## The AMSR colours
plot(r, col = icp$col, zlim = range(icp$breaks),
main = sprintf("NSIDC ice \\% %s", format(getZ(r))))

## End(Not run)

Map data values to colours

Description

If no 'col' is provided, the default image palette is used. The density can be controlled with 'n' and the mapping with the optional 'breaks'. If 'breaks' is included as well as 'n', 'n' is ignored.

Usage

image_pal(x, col, ..., breaks = NULL, n = NULL, zlim = NULL)

image_raster(x, col, ..., breaks = NULL, n = NULL, zlim = NULL)

image_stars(x, col, ..., breaks = NULL, n = NULL, zlim = NULL)

Arguments

Details

The function 'image_pal()' only returns hex character string colours. The function 'image_raster()' will map a raster of numeric values to an RGB 3-layer (channel) raster brick, and 'image_stars()' similarly for a 3-dimensional stars object.

Please note that the expansion to 3-channels is a fairly wasteful thing to do, the overall data is expanded from a single layer to three but this faciliates a specific task of creating textures for 3D mapping, and this is the only way to do it currently. It's also useful in other situations, for controlling exactly the kind of plots we can achieve and for exporting to image formats such as 'GeoTIFF' or 'PNG'.

Value

for 'image_pal()' a vector of hex colours, for 'image_raster' and 'image_stars' a raster or stars object with 3 channel RGB (range 0,255)

Examples

vals <- sort(rnorm(100))
cols <- image_pal(vals, zlim = c(-2.4, .5))
plot(vals, col = cols); abline(h = .5)
points(vals, pch  = ".") ## zlim excluded some of the range

Time-indexed colour.

Description

Create a time-indexed colour map, useful for maintaining an absolute scale across time series as a function of date-time.

Usage

mk_timePal(x, col)

Arguments

Value

function of date-time

Examples

dts <- seq(as.Date("1749-01-01"), by = "1 month", length.out = length(sunspots))
d <- data.frame(date = dts, sunspots = as.vector(t(sunspots)))
tpal <- mk_timePal(d$date, col = sst_pal(50))
par(mfrow  = c(2, 1))
plot(sunspots ~ date, col = tpal(date), data = d)
## colours maintained by absolute date
plot(sunspots ~ date, col = tpal(date), data = d[1500:1800, ], cex = 2)
## we can now insert new points and maintain this colour ramp
d2 <- data.frame(date = seq(min(d$date), max(d$date), by = "5 days"))
d2$sunspots <- approxfun(d$date, d$sunspots)(d2$date)
points(sunspots ~ date, col = tpal(date), data = d2, pch = 19, cex = 0.5)

Sea surface temperature (SST).

Description

SST example raster data set, at 0.25 degree resolution for global coverage in "longitude180/latitude".

Details

Created using script in data-raw/ using 'raadtools' package.

References

Reynolds, et al.(2007) Daily High-resolution Blended Analyses. Available from 'NOAA' search for 'OISST'.

Climatology is based on 1971-2000 OI.v2 SST, Satellite data: Navy NOAA19 METOP AVHRR, Ice data: #' NCEP ice Source: NOAA/National Climatic Data Center.

Examples

dim(oisst)
class(oisst)
image(oisst, useRaster = TRUE)

palr

Description

palr: colours for data

SST colours

Description

SST colours

Usage

sst_pal(x, palette = FALSE, alpha = 1, ...)

sstPal(x, palette = FALSE, alpha = 1, ...)

Arguments

Value

colours, palette, or function, see Details

References

Derived from a file once found at 'http://oceancolor.gsfc.nasa.gov/DOCS/palette_sst.txt'

Examples

data(oisst)
sstcols <- sst_pal(palette = TRUE)
image(oisst, col = sstcols$col, zlim = range(sstcols$breaks))