Note: This document is for an older version of GRASS GIS that will be discontinued soon. You should upgrade, and read the current manual page.
The user provides the map calculation expression. The output map name is automatically extracted from that expression by extracting the string before the '='. If the expression is more complex, the user can also provide the the output map name with the parameter output
Tiles can be defined with the width, height and overlap parameters. If no width and height is specified, they are automatically computed from the number of processes and current computational region (with GRASS GIS v8.2 and above). For example, 8 processes result in 8 tiles where the tile width is equal to the number of columns. If nprocs is higher than one, these tiles will be processed in parallel.
The mapset_prefix parameter ensures that the temporary mapsets created during the tiled processing have unique names. This is useful if the user runs r.mapcalc.tiled several times in parallel (e.g. in an HPC environment).
Option patch_backend can switch how the resulting tiles are merged. With patch_backend=RasterRow (default) the original GridModule implementation is used. With patch_backend=r.patch module r.patch is used with the number of cores specified with nprocs. This backend can only be used with 0 overlap.
g.region raster=ortho_2001_t792_1m r.mapcalc.tiled expression="bright_pixels = if(ortho_2001_t792_1m > 200, 1, 0)" \ width=1000 height=1000 nprocs=4
Available at: r.mapcalc.tiled source code (history)
Latest change: Monday Jan 30 19:52:26 2023 in commit: cac8d9d848299297977d1315b7e90cc3f7698730
Note: This document is for an older version of GRASS GIS that will be discontinued soon. You should upgrade, and read the current manual page.
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© 2003-2023 GRASS Development Team, GRASS GIS 8.2.2dev Reference Manual