t.rast.extract(1grass) GRASS GIS User's Manual t.rast.extract(1grass)
NAME
t.rast.extract - Extracts a subset of a space time raster datasets.
KEYWORDS
temporal, extract, raster, time
SYNOPSIS
t.rast.extract
t.rast.extract --help
t.rast.extract [-n] input=name [where=sql_query] [expression=string]
output=name [basename=string] [suffix=string] [nprocs=integer]
[--overwrite] [--help] [--verbose] [--quiet] [--ui]
Flags:
-n
Register Null maps
--overwrite
Allow output files to overwrite existing files
--help
Print usage summary
--verbose
Verbose module output
--quiet
Quiet module output
--ui
Force launching GUI dialog
Parameters:
input=name [required]
Name of the input space time raster dataset
where=sql_query
WHERE conditions of SQL statement without ’where’ keyword used in
the temporal GIS framework
Example: start_time > ’2001-01-01 12:30:00’
expression=string
r.mapcalc expression assigned to all extracted raster maps
output=name [required]
Name of the output space time raster dataset
basename=string
Basename of the new generated output maps
A numerical suffix separated by an underscore will be attached to
create a unique identifier
suffix=string
Suffix to add at basename: set ’gran’ for granularity, ’time’ for
the full time format, ’num’ for numerical suffix with a specific
number of digits (default %05)
Default: gran
nprocs=integer
Number of r.mapcalc processes to run in parallel
Default: 1
DESCRIPTION
The purpose of t.rast.extract is to extract a subset of a space time
raster dataset and to store that subset in a different space time
raster dataset. The where condition is used to select the subset. In
addition a r.mapcalc sub-expression can be specified that performs op-
erations on all maps of the selected subset. In this expression the
name of the input space time raster dataset can be used as simple map
name. Other STRDS than the input STRDS can not be specified, but any
raster map. In case a r.mapcalc sub-expression is defined, the base
name of the resulting raster maps must be specified. The r.mapcalc ex-
pression can be used to select maps as well, since by default resulting
empty maps are not registered in the output space time raster dataset
and removed after processing. The number of parallel GRASS GIS pro-
cesses can be specified to speed up the processing.
If no r.mapcalc expression is defined, the selected maps are simply
registered in the new created output space time raster dataset to avoid
data duplication.
NOTES
The r.mapcalc sub-expression should not contain the left side "map ="
of a full r.mapcalc expression, only the right side, eg.:
t.rast.extract input=tempmean_monthly where="start_time > ’2010-01-05’" \
output=selected_tempmean_monthly basename=new_tmean_month \
expression="if(tempmean_monthly < 0, null(), tempmean_monthly)"
EXAMPLE
t.rast.extract input=tempmean_monthly output=tempmean_monthly_later_2012 \
where="start_time >= ’2012-01-01’"
t.rast.list tempmean_monthly_later_2012
name|mapset|start_time|end_time
2012_01_tempmean|climate_2000_2012|2012-01-01 00:00:00|2012-02-01 00:00:00
2012_02_tempmean|climate_2000_2012|2012-02-01 00:00:00|2012-03-01 00:00:00
2012_03_tempmean|climate_2000_2012|2012-03-01 00:00:00|2012-04-01 00:00:00
2012_04_tempmean|climate_2000_2012|2012-04-01 00:00:00|2012-05-01 00:00:00
2012_05_tempmean|climate_2000_2012|2012-05-01 00:00:00|2012-06-01 00:00:00
2012_06_tempmean|climate_2000_2012|2012-06-01 00:00:00|2012-07-01 00:00:00
2012_07_tempmean|climate_2000_2012|2012-07-01 00:00:00|2012-08-01 00:00:00
2012_08_tempmean|climate_2000_2012|2012-08-01 00:00:00|2012-09-01 00:00:00
2012_09_tempmean|climate_2000_2012|2012-09-01 00:00:00|2012-10-01 00:00:00
2012_10_tempmean|climate_2000_2012|2012-10-01 00:00:00|2012-11-01 00:00:00
2012_11_tempmean|climate_2000_2012|2012-11-01 00:00:00|2012-12-01 00:00:00
2012_12_tempmean|climate_2000_2012|2012-12-01 00:00:00|2013-01-01 00:00:00
SEE ALSO
t.create, t.info
AUTHOR
Sören Gebbert, Thünen Institute of Climate-Smart Agriculture
SOURCE CODE
Available at: t.rast.extract source code (history)
Accessed: unknown
Main index | Temporal index | Topics index | Keywords index | Graphical
index | Full index
© 2003-2022 GRASS Development Team, GRASS GIS 7.8.7 Reference Manual
GRASS 7.8.7 t.rast.extract(1grass)
Generated by dwww version 1.14 on Sun Dec 29 19:29:32 CET 2024.