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v.what.rast3

Uploads 3D raster values at positions of vector points to the table.

v.what.rast3 map=name [layer=string] raster_3d=name column=name [where=sql_query] [--verbose] [--quiet] [--qq] [--ui]

Example:

v.what.rast3 map=name raster_3d=name column=name

grass.script.run_command("v.what.rast3", map, layer="1", raster_3d, column, where=None, verbose=False, quiet=False, superquiet=False)

Example:

gs.run_command("v.what.rast3", map="name", raster_3d="name", column="name")

Parameters

map=name [required]
    Name of vector points map for which to edit attributes
    Or data source for direct OGR access
layer=string
    Layer number or name
    Vector features can have category values in different layers. This number determines which layer to use. When used with direct OGR access this is the layer name.
    Default: 1
raster_3d=name [required]
    Name of existing 3D raster map to be queried
column=name [required]
    Name of attribute column to be updated with the query result
where=sql_query
    WHERE conditions of SQL statement without 'where' keyword
    Example: income < 1000 and population >= 10000
--help
    Print usage summary
--verbose
    Verbose module output
--quiet
    Quiet module output
--qq
    Very quiet module output
--ui
    Force launching GUI dialog

map : str, required
    Name of vector points map for which to edit attributes
    Or data source for direct OGR access
    Used as: input, vector, name
layer : str, optional
    Layer number or name
    Vector features can have category values in different layers. This number determines which layer to use. When used with direct OGR access this is the layer name.
    Used as: input, layer
    Default: 1
raster_3d : str, required
    Name of existing 3D raster map to be queried
    Used as: input, raster_3d, name
column : str, required
    Name of attribute column to be updated with the query result
    Used as: input, dbcolumn, name
where : str, optional
    WHERE conditions of SQL statement without 'where' keyword
    Example: income < 1000 and population >= 10000
    Used as: input, sql_query, sql_query
verbose: bool, optional
    Verbose module output
    Default: False
quiet: bool, optional
    Quiet module output
    Default: False
superquiet: bool, optional
    Very quiet module output
    Default: False

DESCRIPTION

v.what.rast3 reads 3D raster value for each point in the vector and updates col column in vector attribute table by this value. The column should be type double. This module is based on v.what.rast.
If more points have the same category, attribute value is set to NULL. If 3D raster values is NULL, attribute value is set to NULL.

NOTES

EXAMPLES

A) Reading values from 3D raster map at position of vector points, writing these values into a column of the attribute table connected to the vector map:

v.what.rast3 map=pnts raster3d=plume column=concentration

B) In case of a vector map without attached attribute table, first add a new attribute table. This table is then populated with values queried from the raster map:

# create new random 3d vector points map
v.random -z output=pnts npoints=100 zmin=0  zmax=50

# add new table, link to map
v.db.addtable map=pnts column="concentration double precision"

# query raster map and upload values to vector table into specified column
g.region raster3d=plume -p
v.what.rast3 map=pnts raster3d=plume column=concentration

# verify new attribute table:
v.db.select map=pnts

# verify statistics of uploaded values:
v.univar map=pnts column=concentration type=point

SEE ALSO

v.db.addtable, v.db.select, v.what.rast, v.what.vect, v.univar

AUTHOR

Soeren Gebbert, heavily based on v.what.rast by Radim Blazek

SOURCE CODE

Available at: v.what.rast3 source code (history)
Latest change: Friday Feb 07 19:16:09 2025 in commit a82a39f