DESCRIPTION

The purpose of this module is the creation of space time datasets of type raster (STRDS), 3D raster (STR3DS) and vector (STVDS).

Space time datasets represent spatio-temporal fields in the temporal GRASS framework. They are designed to collect any amount of time stamped maps with time intervals and time instances. The temporal type of a space time dataset can be absolute or relative and must be set on dataset creation besides the name and the description.

Time stamped maps can registered in and unregistered from space time datasets. The spatio-temporal extent as well as the metadata of a space time dataset is derived from its registered maps. Hence the metadata is dependent from the dataset type (raster, 3D raster, vector).

EXAMPLE

In this example we create 7 raster maps using r.mapcalc with random values that will be registered in a single space time raster dataset named precipitation_daily using a daily temporal granularity. The names of the raster maps are stored in a text file that is used for raster map registration. We use t.create for the space time raster dataset creation and t.register to register the raster maps in the space time raster dataset. At the end we report informations about the space time raster dataset to stdout using t.info. 

MAPS="map_1 map_2 map_3 map_4 map_5 map_6 map_7"

for map in ${MAPS} ; do
    r.mapcalc --o expr="${map} = rand(0, 10)" 
    echo ${map} >> map_list.txt 
done

t.create type=strds temporaltype=absolute \
         output=precipitation_daily \
         title="Daily precipitation" \
         description="Test dataset with daily precipitation"

t.register -i type=rast input=precipitation_daily \
           file=map_list.txt start=20-08-2012 increment="1 days"

t.info type=strds input=precipitation_daily

 +-------------------- Space Time Raster Dataset -----------------------------+
 |                                                                            |
 +-------------------- Basic information -------------------------------------+
 | Id: ........................ precipitation_daily@PERMANENT
 | Name: ...................... precipitation_daily
 | Mapset: .................... PERMANENT
 | Creator: ................... soeren
 | Creation time: ............. 2012-10-16 00:20:28.920018
 | Temporal type: ............. absolute
 | Semantic type:.............. mean
 +-------------------- Absolute time -----------------------------------------+
 | Start time:................. 2012-08-27 00:00:00
 | End time:................... 2012-09-03 00:00:00
 | Granularity:................ 1 days
 | Temporal type of maps:...... interval
 +-------------------- Spatial extent ----------------------------------------+
 | North:...................... 70.0
 | South:...................... 0.0
 | East:.. .................... 100.0
 | West:....................... 0.0
 | Top:........................ 0.0
 | Bottom:..................... 0.0
 +-------------------- Metadata information ----------------------------------+
 | Number of registered maps:.. 7
 | Title:
 | Daily precipitation
 | Description:
 | Test dataset with daily precipitation
 | North-South resolution min:. 10.0
 | North-South resolution max:. 10.0
 | East-west resolution min:... 10.0
 | East-west resolution max:... 10.0
 | Minimum value min:.......... 0.0
 | Minimum value max:.......... 0.0
 | Maximum value min:.......... 9.0
 | Maximum value max:.......... 9.0
 | Raster register table:...... precipitation_daily_PERMANENT_raster_register
 +----------------------------------------------------------------------------+

SEE ALSO

t.register, t.info

AUTHOR

Sören Gebbert

Last changed: $Date$