`divergingx_hcl.Rd`

Diverging HCL color palettes generated through combination of two fully flexible (and possibly unbalanced) multi-hue sequential palettes.

divergingx_hcl( n, palette = "Geyser", ..., fixup = TRUE, alpha = 1, rev = FALSE, h1, h2, h3, c1, c2, c3, l1, l2, l3, p1, p2, p3, p4, cmax1, cmax2 ) divergingx_palettes(palette = NULL, plot = FALSE, n = 7L, ...)

n | the number of colors (\(\ge 1\)) to be in the palette. |
---|---|

palette | character with the name (see details). |

... | arguments passed to |

fixup | logical. Should the color be corrected to a valid RGB value? |

alpha | numeric vector of values in the range |

rev | logical. Should the palette be reversed? |

h1 | numeric. Starting hue coordinate. |

h2 | numeric. Center hue coordinate. |

h3 | numeric. Ending hue coordinate. |

c1 | numeric. Chroma coordinate corresponding to |

c2 | numeric. Chroma coordinate corresponding to |

c3 | numeric. Chroma coordinate corresponding to |

l1 | numeric. Luminance coordinate corresponding to |

l2 | numeric. Luminance coordinate corresponding to |

l3 | numeric. Luminance coordinate corresponding to |

p1 | numeric. Power parameter for chroma coordinates in first sequential palette. |

p2 | numeric. Power parameter for luminance coordinates in first sequential palette (if |

p3 | numeric. Power parameter for chroma coordinates in second sequential palette (if |

p4 | numeric. Power parameter for luminance coordinates in second sequential palette (if |

cmax1 | numeric. Maximum chroma coordinate in first sequential palette (not used if |

cmax2 | numeric. Maximum chroma coordinate in second sequential palette (if |

plot | logical. Should the selected HCL color palettes be visualized? |

A character vector with (s)RGB codings of the colors in the palette.

The `divergingx_hcl`

function simply calls `sequential_hcl`

twice with a prespecified set of hue, chroma, and luminance parameters. This is
similar to `diverging_hcl`

but allows for more flexibility:
`diverging_hcl`

employs two *single-hue* sequential palettes,
always uses zero chroma for the neutral/central color, and restricts the
chroma/luminance path to be the same in both “arms” of the palette.
In contrast, `divergingx_hcl`

relaxes this to two full *multi-hue*
palettes that can thus go through a non-gray neutral color (typically light
yellow). Consequently, the chroma/luminance paths can be rather unbalanced
between the two arms.

With this additional flexibility various diverging palettes suggested by https://ColorBrewer2.org/ and CARTO (https://carto.com/carto-colors/), can be emulated along with the Zissou 1 palette from wesanderson, Cividis from viridis, and Roma from scico.

Available CARTO palettes: ArmyRose, Earth, Fall, Geyser, TealRose, Temps, and
Tropic (with Tropic also available in `diverging_hcl`

).

Available ColorBrewer.org palettes: PuOr, RdBu, RdGy, PiYG, PRGn, BrBG, RdYlBu, RdYlGn, Spectral.

Zeileis A, Fisher JC, Hornik K, Ihaka R, McWhite CD, Murrell P, Stauffer R, Wilke CO (2020).
“colorspace: A Toolbox for Manipulating and Assessing Colors and Palettes.”
*Journal of Statistical Software*, **96**(1), 1--49. doi: 10.18637/jss.v096.i01

## show emulated CARTO/ColorBrewer.org palettes divergingx_palettes(plot = TRUE)## compared to diverging_hcl() the diverging CARTO palettes are typically warmer ## but also less balanced with respect to chroma/luminance, see e.g., specplot(divergingx_hcl(7, "ArmyRose"))