r.volume generates a table containing the sum of all cells from a input raster map sorted by category on a clump raster map, and optionally generates a vector points map of the centroids for each clump. If a clump map is not specified, the current MASK is used. The MASK can be defined by r.mask. The sum is multiplied by the area of a cell to give the volume occupied by that cell. See below for an example of the output table.
If a clump map is not given and a MASK not set, the program exits with an error message.
r.volume works in the current region and respects the current MASK.
Attribute table linked to the vector map with centroids contains several columns:
Vector points can be converted directly to a raster map with each point a separate category using v.to.rast.
# set computational region g.region raster=elevation # compute volume r.volume input=elevation clump=geology_30m Volume report on data from <elevation> using clumps on <geology_30m> raster map Category Average Data # Cells Centroid Total Number in clump Total in clump Easting Northing Volume ----------------------------------------------------------------------------- 217 118.93 86288828 725562 635325.00 221535.00 8628882798.63 262 108.97 21650560 198684 638935.00 222495.00 2165056037.02 270 92.23 63578874 689373 642405.00 221485.00 6357887443.53 405 132.96 33732662 253710 631835.00 224095.00 3373266208.59 583 139.35 3011288 21609 630205.00 224665.00 301128821.55 720 124.30 599618 4824 634075.00 227995.00 59961816.06 766 132.43 936791 7074 631425.00 227845.00 93679120.08 862 118.31 7302317 61722 630505.00 218885.00 730231746.74 910 94.20 4235816 44964 639215.00 216365.00 423581613.11 921 135.22 1693985 12528 630755.00 215445.00 169398523.05 945 127.24 1145 9 630015.00 215015.00 114512.03 946 89.91 365748 4068 639085.00 215255.00 36574833.85 948 129.02 112632 873 630185.00 215115.00 11263181.57 ----------------------------------------------------------------------------- Total Volume = 22351026655.81
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