r.colors.stddev(1grass)

✨ r.colors.stddev ✨

omg hi bestie 💖 welcome to r.colors.stddev(1grass), straight outta the GRASS User's Manual. this one's a little raster-color-table fairy godmother and she is so underrated, no cap. let's get into it 🧚

🌸 NAME 🌸

r.colors.stddev — sets color rules based on stddev from a raster map's mean value. literally that's her whole job and she does it flawlessly 💅

🎀 KEYWORDS 🎀

raster, color table

✨ SYNOPSIS ✨

r.colors.stddev
r.colors.stddev --help
r.colors.stddev [-bz] map=name  [--help]  [--verbose]  [--quiet]  [--ui]

🦋 Flags:

• -b — color using standard deviation bands (the cute lil rainbow-stripe mode 🌈)
• -z — force center at zero (for when your data is a differences map and zero is the moment 👑)
• --help — print usage summary
• --verbose — verbose module output
• --quiet — quiet module output
• --ui — force launching GUI dialog

💜 Parameters:

• map=name [required] — name of raster map

yes bestie, map is required. she's not doing anything without it, periodt.

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🩷 DESCRIPTION 🩷

okay so r.colors.stddev sets raster map color rules based on standard deviations from a map's mean value. and it can do it two ways, which is giving versatility fr fr:

• as a continuous color gradient 🌈, or
• in color bands per standard deviation (S.D.) from the mean 🎨

with the color band option (-b), here's the tea — values less than 1 S.D. from the mean get colored green, within 1-2 S.D. get yellow, within 2-3 S.D. get red, and beyond 3 S.D. get black. iconic gradient of chaos, honestly 💀

for a differences map there's an option to lock the center of the color table at zero (-z, the moment). values more than two S.D. below the mean will be colored blue; values below the mean but less than 2 S.D. away will transition to white, and above the mean the colors will similarly transition to full red at +2 S.D. 🫶

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🔥 EXAMPLE 🔥

north carolina sample dataset, the classic, the legend:

g.region raster=elevation -p
r.colors.stddev elevation

Figure: Standard deviations from mean elevation 📊✨

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👀 SEE ALSO 👀

• r.colors
• r.univar
• v.colors

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🌟 AUTHOR 🌟

Hamish Bowman, Dunedin, New Zealand 🫶

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💾 SOURCE CODE 💾

Available at: r.colors.stddev source code (history)

Latest change: Monday May 19 11:52:48 2025 in commit: 01f1bb44b9df33803e83b9e3c52a28102000f6d8

Main index | Raster index | Topics index | Keywords index | Graphical index | Full index

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🥺 and that's the whole page bestie, you understood it, you ate, no crumbs left.

© 2003-2026 GRASS Development Team, GRASS 8.5.0 Reference Manual — this was GRASS 8.5.0, r.colors.stddev(1grass), and you're officially a color-table girlie now 💖🌈👑