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

6       t.rast.neighbors   - Performs a neighborhood analysis for each map in a
7       space time raster dataset.
8

KEYWORDS

10       temporal, aggregation, raster, time
11

SYNOPSIS

13       t.rast.neighbors
14       t.rast.neighbors --help
15       t.rast.neighbors  [-nr]   input=name   output=name    [where=sql_query]
16       [size=integer]     method=string    basename=string     [suffix=string]
17       [nprocs=integer]    [--overwrite]   [--help]   [--verbose]    [--quiet]
18       [--ui]
19
20   Flags:
21       -n
22           Register Null maps
23
24       -r
25           Ignore the current region settings and use the raster map regions
26
27       --overwrite
28           Allow output files to overwrite existing files
29
30       --help
31           Print usage summary
32
33       --verbose
34           Verbose module output
35
36       --quiet
37           Quiet module output
38
39       --ui
40           Force launching GUI dialog
41
42   Parameters:
43       input=name [required]
44           Name of the input space time raster dataset
45
46       output=name [required]
47           Name of the output space time raster dataset
48
49       where=sql_query
50           WHERE  conditions  of SQL statement without ’where’ keyword used in
51           the temporal GIS framework
52           Example: start_time > ’2001-01-01 12:30:00’
53
54       size=integer
55           Neighborhood size
56           Default: 3
57
58       method=string [required]
59           Aggregate operation to be performed on the raster maps
60           Options: average, median, mode, minimum,  maximum,  range,  stddev,
61           sum,  count,  variance,  diversity,  interspersion, quart1, quart3,
62           perc90, quantile
63           Default: average
64
65       basename=string [required]
66           Basename of the new generated output maps
67           A numerical suffix separated by an underscore will be  attached  to
68           create a unique identifier
69
70       suffix=string
71           Suffix  to  add at basename: set ’gran’ for granularity, ’time’ for
72           the full time format, ’num’ for numerical suffix  with  a  specific
73           number of digits (default %05)
74           Default: gran
75
76       nprocs=integer
77           Number of r.neighbor processes to run in parallel
78           Default: 1
79

DESCRIPTION

81       t.rast.neighbors  performs  r.neighbors  computations  on the maps of a
82       space time raster dataset (STRDS). This module  supports  a  subset  of
83       options that are available in r.neighbors. The size of the neighborhood
84       and the aggregation method can be chosen.
85
86       The user must provide an input and an output space time raster  dataset
87       and the basename of the resulting raster maps. The resulting STRDS will
88       have the same temporal resolution as the input dataset.  All maps  will
89       be processed using the current region settings.
90
91       The user can select a subset of the input space time raster dataset for
92       processing using a SQL WHERE statement. The number of CPU’s to be  used
93       for  parallel  processing  can  be  specified with the nprocs option to
94       speedup the computation on multi-core system.
95

EXAMPLE

97       To smooth the maps contained in a space time dataset run:
98       t.rast.neighbors input=tempmean_monthly output=smooth_tempmean_monthly \
99                        basename=tmean_smooth size=5 method=average nprocs=4
100       # show some info about the new space time dataset
101       t.info smooth_tempmean_monthly
102        +-------------------- Space Time Raster Dataset -----------------------------+
103        |                                                                            |
104        +-------------------- Basic information -------------------------------------+
105        | Id: ........................ smooth_tempmean_monthly@climate_2000_2012
106        | Name: ...................... smooth_tempmean_monthly
107        | Mapset: .................... climate_2000_2012
108        | Creator: ................... lucadelu
109        | Temporal type: ............. absolute
110        | Creation time: ............. 2014-11-27 11:41:36.444579
111        | Modification time:.......... 2014-11-27 11:41:39.978232
112        | Semantic type:.............. mean
113        +-------------------- Absolute time -----------------------------------------+
114        | Start time:................. 2009-01-01 00:00:00
115        | End time:................... 2013-01-01 00:00:00
116        | Granularity:................ 1 month
117        | Temporal type of maps:...... interval
118        +-------------------- Spatial extent ----------------------------------------+
119        | North:...................... 320000.0
120        | South:...................... 10000.0
121        | East:.. .................... 935000.0
122        | West:....................... 120000.0
123        | Top:........................ 0.0
124        | Bottom:..................... 0.0
125        +-------------------- Metadata information ----------------------------------+
126        | Raster register table:...... raster_map_register_ea1c9a83524e41a784d72744b08c6107
127        | North-South resolution min:. 500.0
128        | North-South resolution max:. 500.0
129        | East-west resolution min:... 500.0
130        | East-west resolution max:... 500.0
131        | Minimum value min:.......... -6.428905
132        | Minimum value max:.......... 18.867296
133        | Maximum value min:.......... 4.247691
134        | Maximum value max:.......... 28.767953
135        | Aggregation type:........... None
136        | Number of registered maps:.. 48
137        |
138        | Title:
139        | Monthly precipitation
140        | Description:
141        | Dataset with monthly precipitation
142        | Command history:
143        | # 2014-11-27 11:41:36
144        | t.rast.neighbors input="tempmean_monthly"
145        |     output="smooth_tempmean_monthly" basename="tmean_smooth" size="5"
146        |     method="average" nprocs="4"
147        |
148        +----------------------------------------------------------------------------+
149       # now compare the values between the original and the smoothed dataset
150       t.rast.list input=smooth_tempmean_monthly columns=name,start_time,min,max
151       name|start_time|min|max
152       tmean_smooth_1|2009-01-01 00:00:00|-3.361714|7.409861
153       tmean_smooth_2|2009-02-01 00:00:00|-1.820261|7.986794
154       tmean_smooth_3|2009-03-01 00:00:00|2.912971|11.799684
155       ...
156       tmean_smooth_46|2012-10-01 00:00:00|9.38767|18.709297
157       tmean_smooth_47|2012-11-01 00:00:00|1.785653|10.911189
158       tmean_smooth_48|2012-12-01 00:00:00|1.784212|11.983857
159       t.rast.list input=tempmean_monthly columns=name,start_time,min,max
160       name|start_time|min|max
161       2009_01_tempmean|2009-01-01 00:00:00|-3.380823|7.426054
162       2009_02_tempmean|2009-02-01 00:00:00|-1.820261|8.006386
163       2009_03_tempmean|2009-03-01 00:00:00|2.656992|11.819274
164       ...
165       2012_10_tempmean|2012-10-01 00:00:00|9.070884|18.709297
166       2012_11_tempmean|2012-11-01 00:00:00|1.785653|10.911189
167       2012_12_tempmean|2012-12-01 00:00:00|1.761019|11.983857
168

SEE ALSO

170        r.neighbors, t.rast.aggregate.ds,  t.rast.extract,  t.info,  g.region,
171       r.mask
172

AUTHOR

174       Sören Gebbert, Thünen Institute of Climate-Smart Agriculture
175

SOURCE CODE

177       Available at: t.rast.neighbors source code (history)
178
179       Main index | Temporal index | Topics index | Keywords index | Graphical
180       index | Full index
181
182       © 2003-2019 GRASS Development Team, GRASS GIS 7.8.2 Reference Manual
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186GRASS 7.8.2                                                t.rast.neighbors(1)
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