t.rast.extract(1grass)

1t.rast.extract(1)             Grass User's Manual            t.rast.extract(1)
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NAME

6       t.rast.extract  - Extracts a subset of a space time raster datasets.
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KEYWORDS

9       temporal, extract, raster, time
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SYNOPSIS

12       t.rast.extract
13       t.rast.extract --help
14       t.rast.extract [-n] input=name  [where=sql_query]   [expression=string]
15       output=name   [basename=string]    [suffix=string]     [nprocs=integer]
16       [--overwrite]  [--help]  [--verbose]  [--quiet]  [--ui]
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18   Flags:
19       -n
20           Register Null maps
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22       --overwrite
23           Allow output files to overwrite existing files
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25       --help
26           Print usage summary
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28       --verbose
29           Verbose module output
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31       --quiet
32           Quiet module output
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34       --ui
35           Force launching GUI dialog
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37   Parameters:
38       input=name [required]
39           Name of the input space time raster dataset
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41       where=sql_query
42           WHERE  conditions  of SQL statement without ’where’ keyword used in
43           the temporal GIS framework
44           Example: start_time > ’2001-01-01 12:30:00’
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46       expression=string
47           r.mapcalc expression assigned to all extracted raster maps
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49       output=name [required]
50           Name of the output space time raster dataset
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52       basename=string
53           Basename of the new generated output maps
54           A numerical suffix separated by an underscore will be  attached  to
55           create a unique identifier
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57       suffix=string
58           Suffix  to  add at basename: set ’gran’ for granularity, ’time’ for
59           the full time format, ’num’ for numerical suffix  with  a  specific
60           number of digits (default %05)
61           Default: gran
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63       nprocs=integer
64           Number of r.mapcalc processes to run in parallel
65           Default: 1
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DESCRIPTION

68       The  purpose  of  t.rast.extract is to extract a subset of a space time
69       raster dataset and to store that  subset  in  a  different  space  time
70       raster  dataset.  The  where condition is used to select the subset. In
71       addition a r.mapcalc sub-expression  can  be  specified  that  performs
72       operations  on all maps of the selected subset.  In this expression the
73       name of the input space time raster dataset can be used as  simple  map
74       name.  Other  STRDS  than the input STRDS can not be specified, but any
75       raster map. In case a r.mapcalc sub-expression  is  defined,  the  base
76       name  of  the  resulting  raster  maps must be specified. The r.mapcalc
77       expression can be used to select maps as well, since by default result‐
78       ing  empty  maps  are  not  registered  in the output space time raster
79       dataset and removed after processing. The number of parallel GRASS  GIS
80       processes can be specified to speed up the processing.
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82       If  no  r.mapcalc  expression  is defined, the selected maps are simply
83       registered in the new created output space time raster dataset to avoid
84       data duplication.
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NOTES

87       The  r.mapcalc  sub-expression should not contain the left side "map ="
88       of a full r.mapcalc expression, only the right side, eg.:
89       t.rast.extract input=tempmean_monthly where="start_time > ’2010-01-05’" \
90                      output=selected_tempmean_monthly basename=new_tmean_month \
91                      expression="if(tempmean_monthly < 0, null(), tempmean_monthly)"
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EXAMPLE

94       t.rast.extract input=tempmean_monthly output=tempmean_monthly_later_2012 \
95                      where="start_time >= ’2012-01-01’"
96       t.rast.list tempmean_monthly_later_2012
97       name|mapset|start_time|end_time
98       2012_01_tempmean|climate_2000_2012|2012-01-01 00:00:00|2012-02-01 00:00:00
99       2012_02_tempmean|climate_2000_2012|2012-02-01 00:00:00|2012-03-01 00:00:00
100       2012_03_tempmean|climate_2000_2012|2012-03-01 00:00:00|2012-04-01 00:00:00
101       2012_04_tempmean|climate_2000_2012|2012-04-01 00:00:00|2012-05-01 00:00:00
102       2012_05_tempmean|climate_2000_2012|2012-05-01 00:00:00|2012-06-01 00:00:00
103       2012_06_tempmean|climate_2000_2012|2012-06-01 00:00:00|2012-07-01 00:00:00
104       2012_07_tempmean|climate_2000_2012|2012-07-01 00:00:00|2012-08-01 00:00:00
105       2012_08_tempmean|climate_2000_2012|2012-08-01 00:00:00|2012-09-01 00:00:00
106       2012_09_tempmean|climate_2000_2012|2012-09-01 00:00:00|2012-10-01 00:00:00
107       2012_10_tempmean|climate_2000_2012|2012-10-01 00:00:00|2012-11-01 00:00:00
108       2012_11_tempmean|climate_2000_2012|2012-11-01 00:00:00|2012-12-01 00:00:00
109       2012_12_tempmean|climate_2000_2012|2012-12-01 00:00:00|2013-01-01 00:00:00
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AUTHOR

115       Sören Gebbert, Thünen Institute of Climate-Smart Agriculture
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117       Last changed: $Date: 2015-09-22 10:10:38 +0200 (Tue, 22 Sep 2015) $
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SOURCE CODE

120       Available at: t.rast.extract source code (history)
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122       Main index | Temporal index | Topics index | Keywords index | Graphical
123       index | Full index
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125       © 2003-2019 GRASS Development Team, GRASS GIS 7.4.4 Reference Manual
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129GRASS 7.4.4                                                  t.rast.extract(1)