topic_algebra(1)

✨ Topic: algebra ✨

okay bestie, welcome to the algebra topic page of the GRASS GIS manual 💅 this is the little corner of the docs where all the math-y, expression-y, neighborhood-y tools live, and ngl it's a whole vibe. Every one of these is a real program, and every one of them is here for you 🫶

• r.mapcalc — the Raster map calculator. it does the math on rasters, iconic behavior honestly.
• r.mapcalc.simple — calculates a brand new raster map from a simple r.mapcalc expression. like r.mapcalc but keeping it cute and uncomplicated 🎀
• r.mfilter — performs raster map matrix filter. yes queen, filter that matrix.
• r.neighbors — takes each cell's category value and makes it a function of the category values of all the cells around it, then stores those new cell values into an output raster map layer. neighborhood drama, but make it math 🦋
• r.quantile — computes quantiles using two passes. two passes, no cap.
• r.texture — generates images with textural features from a raster map. texture?? in my raster?? it's giving fabric ✨
• r3.mapcalc — the Raster map calculator, but for 3D rasters. the 3 is for three-dimensional, bestie, keep up 💜
• r3.neighbors — takes each voxel value and makes it a function of the values assigned to the voxels around it, and stores the new voxel values in an output 3D raster map. voxel friendship circle 🧚
• t.rast.algebra — applies temporal and spatial operations on space time raster datasets using temporal raster algebra. it's algebra but it knows what time it is ⭐
• t.rast.mapcalc — performs spatio-temporal mapcalc expressions on temporally sampled maps of space time raster datasets. say that five times fast, I dare you 😭
• t.rast3d.algebra — applies temporal and spatial operations on space time 3D raster datasets using temporal 3D raster algebra. 3D and time?? main character energy 👑
• t.rast3d.mapcalc — performs r3.mapcalc expressions on maps of sampled space time 3D raster datasets. yep, the 3D one again, but with sampling 🌈
• t.vect.algebra — applies temporal and spatial operations on space time vector datasets using temporal vector algebra. vectors said "me too" 💖
• v.neighbors — neighborhood analysis tool for vector point maps. points with neighbors, so basically a group chat 🌸

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also, lowkey important: see also the corresponding keyword algebra for additional references. iykyk 🔥

if you wanna wander further, the indexes are right there for you:

• Main index | Topics index | Keywords index | Graphical index | Full index

heads up bestie: this page is part of the GRASS GIS 8.4.2 Reference Manual, and the whole thing is © 2003-2025 GRASS Development Team 💖 respect the copyright, it's the law fr fr.

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okay that's the whole page, mwah 💅 this was topic_algebra(1) from the GRASS GIS User's Manual, brought to you by GRASS 8.4.2. go do some algebra, you're gonna ate it 🎀✨