Therefore, as space-time datasets are mapset specific, they can only register raster, 3D raster or vector maps from the same mapset.
By default, space-time datasets can not register maps from other mapsets. This is a security measure, since the registration of maps in a space-time dataset will always modify the metadata of the registered map. This is critical if:
Connection settings are performed with t.connect. By default, a SQLite3 database is created in the current mapset to store all space-time datasets and registered time series maps in that mapset.
New space-time datasets are created in the temporal database with t.create. The name of the new dataset, the type (strds, str3ds, stvds), the title and the description must be provided for creation. Optionally, the temporal type (absolute, relative) and the semantic information can be provided.
The module t.register is designed to register raster, 3D raster and vector maps in the temporal database and in the space-time datasets. It supports different input options. Maps to register can be provided as a comma separated string at the command line, or in an input file. The module supports the definition of time stamps (time instances or intervals) for each map in the input file. With t.unregister maps can be unregistered from space-time datasets and from the temporal database.
Use only temporal commands like t.register to attach a time stamp to raster, 3D raster and vector maps. The commands r.timestamp, r3.timestamp and v.timestamp should not be used because they only modify the metadata of the map in the spatial database, but they do not register maps in the temporal database. However, maps with timestamps attached by means of *.timestamp modules can be registered in space-time datasets using the existing timestamp.
The module t.remove will remove the space-time datasets from the temporal database and optionally all registered maps. It will take care of multiple map registration, hence if maps are registered in several space-time datasets in the current mapset. Use t.support to modify the metadata of space time datasets or to update the metadata that is derived from registered maps. This module also checks for removed and modified maps and updates the space-time datasets accordingly. Rename a space-time dataset with t.rename.
To print information about space-time datasets or registered maps, the module t.info can be used. t.list will list all space-time datasets and registered maps in the temporal database.
The module t.topology was designed to compute and check the temporal topology of space-time datasets. Moreover, the module t.sample samples input space-time dataset(s) with a sample space-time dataset and prints the result to standard output. Different sampling methods are supported and can be combined.
List of general management modules:
Several modules in the temporal framework have a where option.
This option allows performing different selections of maps registered
in the temporal database and in space-time datasets. The columns that
can be used to perform these selections are: id, name, creator,
mapset, temporal_type, creation_time, start_time, end_time, north,
south, west, east, nsres, ewres, cols, rows, number_of_cells, min and
max. Note that for vector time series, i.e. stvds, some of the
columns that can be queried to list/select vector maps differ from
those for space-time raster datasets (check with
Moreover, there is v.what.strds, that uploads space-time raster dataset values at positions of vector points, to the attribute table of the vector map.
The module t.rast.to.rast3 converts space-time raster datasets into space-time voxel cubes. All 3D raster modules can be used to process such voxel cubes. This conversion allows the export of space-time raster datasets as netCDF files that include time as one dimension.
Available at: Temporal data processing in GRASS GIS source code (history)
Latest change: Saturday Mar 11 22:02:30 2023 in commit: 1e2ac5a211199b2b87bc0d0c4c46220f0cbf782e
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