1t.rast.neighbors(1) Grass User's Manual t.rast.neighbors(1)
2
6 t.rast.neighbors - Performs a neighborhood analysis for each map in a
7 space time raster dataset.
8
10 temporal, aggregation, raster, time
11
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 Flags:
21 -n
22 Register Null maps
23 -r
25 Ignore the current region settings and use the raster map regions
26 --overwrite
28 Allow output files to overwrite existing files
29 --help
31 Print usage summary
32 --verbose
34 Verbose module output
35 --quiet
37 Quiet module output
38 --ui
40 Force launching GUI dialog
41 Parameters:
43 input=name [required]
44 Name of the input space time raster dataset
45 output=name [required]
47 Name of the output space time raster dataset
48 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 size=integer
55 Neighborhood size
56 Default: 3
57 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 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 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 nprocs=integer
77 Number of r.neighbor processes to run in parallel
78 Default: 1
79
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 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 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
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
170 r.neighbors, t.rast.aggregate.ds, t.rast.extract, t.info, g.region,
171 r.mask
172
174 Sören Gebbert, Thünen Institute of Climate-Smart Agriculture
175 Last changed: $Date: 2016-10-27 23:20:55 +0200 (Thu, 27 Oct 2016) $
177
179 Available at: t.rast.neighbors source code (history)
180 Main index | Temporal index | Topics index | Keywords index | Graphical
182 index | Full index
183 © 2003-2019 GRASS Development Team, GRASS GIS 7.4.4 Reference Manual
185GRASS 7.4.4 t.rast.neighbors(1)