Convert visible wavelengths to Hex values in R.
# Install from GitHub:
install.packages("devtools")
# devtools::install_github("roaldarbol/wavecolour")
install.packages("wavecolour", repos = c('https://roaldarbol.r-universe.dev', 'https://cloud.r-project.org'))
wavecolour supplies 3 low-level functions for converting wavelengths into colour codes:
wavelength_to_hex()wavelength_to_rgb()rgb_to_hex()Additionally, it supplies a colour palette which can be used with ggplot2 as:
scale_colour_wavelength() / scale_color_wavelength()
scale_fill_wavelength()The scales are opinionated, and will return black for anything outside the visible spectrum (380 to 750). If you just need a palette with these colours, the rainbow palette is the way to go - however, I would highly advise you to choose a better alternative, e.g. viridis.
# Create single colour
col <- wavelength_to_hex(560)
# Create palette
wavelengths <- seq(from = 380, to = 750, by = 1)
hex_pal <- sapply(wavelengths, wavelength_to_hex)
rgb_pal <- sapply(wavelengths, wavelength_to_rgb)
library(ggplot2)
library(dplyr)
library(wavecolour)
# Create data
wavl <- seq(from = 300, to = 790, length.out = 500)
wavl_sin <- sin((wavl * pi) / (180)) + 1.5
wavl <- bind_cols(wavl, wavl_sin)
names(wavl) <- c("wavelength", "intensity")
# Create plot
ggplot(wavl, aes(wavelength, intensity)) +
geom_segment(aes(xend=wavelength, yend=0, colour = wavelength), size = 1) +
geom_line() +
scale_colour_wavelength() +
theme_minimal()
Adapted from Noah's Python implementation, who adapted from Dan Bruton's Fortran implementation.