v.category(1)

1v.category(1)                 Grass User's Manual                v.category(1)
2
3
4

NAME

6       v.category   - Attach, delete or report vector categories to map geome‐
7       try.
8

KEYWORDS

10       vector
11

SYNOPSIS

13       v.category
14       v.category help
15       v.category [-g] input=name  [output=name]    [type=string[,string,...]]
16       [option=string]       [cat=integer]       [layer=integer[,integer,...]]
17       [step=integer]   [--overwrite]  [--verbose]  [--quiet]
18
19   Flags:
20       -g
21           Shell script style, currently only for report
22           Format: layer type count min max
23
24       --overwrite
25           Allow output files to overwrite existing files
26
27       --verbose
28           Verbose module output
29
30       --quiet
31           Quiet module output
32
33   Parameters:
34       input=name
35           Name of input vector map
36
37       output=name
38           Name for output vector map
39
40       type=string[,string,...]
41           Type
42           Feature type(s)
43           Options: point,line,boundary,centroid,area
44           Default: point,line,boundary,centroid,area
45
46       option=string
47           Action to be done
48           Options: add,del,chlayer,sum,report,print
49           Default: add
50           add: add a new category
51           del: delete category
52           chlayer: change layer number (e.g. layer=3,1  changes  layer  3  to
53           layer 1)
54           sum:  add the value specified by cat option to the current category
55           value
56           report: print report (statistics), in shell style: layer type count
57           min max
58           print: print category values, more cats in the same layer are sepa‐
59           rated by '/'
60
61       cat=integer
62           Category value
63           Default: 1
64
65       layer=integer[,integer,...]
66           Layer number
67           A single vector map can be connected to multiple  database  tables.
68           This number determines which table to use.
69           Default: 1
70
71       step=integer
72           Category increment
73           Default: 1
74

DESCRIPTION

76       v.category attaches, deletes or reports vector categories to map geome‐
77       try. These categories (IDs) are  used  to  link  a  vector  map  to  an
78       attribute table.
79

NOTES

81       Use v.to.db to upload related categories to a linked attribute table.
82
83       The  type parameter specifies the type of geometry objects to which the
84       category is added; it is similar to an input filter - only the geometry
85       specified in 'type' is processed.
86
87       If  the  type parameter is set to centroid and the option parameter set
88       to add, new categories will be added to existing centroids.  Note  how‐
89       ever,  that  new  centroids cannot be created this way.  To do so, they
90       must be added manually using v.digit or by running v.category with  the
91       type parameter set to area (see below also).
92
93       Areas are a special case because it is impossible to attach a cat to an
94       area without a centroid; in this case, the module places new  centroids
95       in areas automatically.
96

EXAMPLES

98       1) Report vector categories
99
100       v.category in=testmap option=report
101       LAYER/TABLE 1/testmap:
102       type       count        min        max
103       point          0          0          0
104       line        1379          1       1379
105       boundary       0          0          0
106       centroid       0          0          0
107       area           0          0          0
108       all         1379          1       1379
109
110
111       2) Delete all vector categories in layer 1
112
113       v.category in=testmap out=outmap option=del
114
115
116       3) Add vector categories in layer 1 with step=2
117
118       v.category in=outmap out=stepmap option=add step=2
119       LAYER/TABLE 1/outmap:
120       type       count        min        max
121       point          0          0          0
122       line        1379          1       2757
123       boundary       0          0          0
124       centroid       0          0          0
125       area           0          0          0
126       all         1379          1       2757
127
128
129       4) Add categories/centroids to a vector map without categories
130
131       v.category in=wkt out=wktnew option=add
132
133
134       Results can be tested using d.what.vect.
135

AUTHOR

140       Radim Blazek, ITC-Irst, Trento, Italy
141
142       Last changed: $Date: 2006-08-31 16:06:33 +0200 (Thu, 31 Aug 2006) $
143
144       Full index
145
146       © 2003-2008 GRASS Development Team
147
148
149
150GRASS 6.3.0                                                      v.category(1)