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Note: This document is for an older version of GRASS GIS that will be discontinued soon. You should upgrade, and read the current manual page.


v.edit - Edits a vector map, allows adding, deleting and modifying selected vector features.


vector, geometry, editing, line, node, point, vertex, level1


v.edit --help
v.edit [-rcnb1p] map=name [layer=string] [type=string[,string,...]] tool=string [input=name] [move=x,y,z] [threshold=float[,float,...]] [ids=range] [cats=range] [coords=x,y[,x,y,...]] [bbox=x1,y1,x2,y2] [polygon=x,y[,x,y,...]] [where=sql_query] [query=string] [bgmap=name[,name,...]] [snap=string] [zbulk=value,step] [--overwrite] [--help] [--verbose] [--quiet] [--ui]


Reverse selection
Close added boundaries (using threshold distance)
Do not expect header of input data
Do not build topology
Advantageous when handling a large number of points
Modify only first found feature in bounding box
Connect parallel lines (using extend tools and threshold distance)
Allow output files to overwrite existing files
Print usage summary
Verbose module output
Quiet module output
Force launching GUI dialog


map=name [required]
Name of vector map to edit
Or data source for direct OGR access
Layer number or name
Vector features can have category values in different layers. This number determines which layer to use. When used with direct OGR access this is the layer name.
Default: 1
Input feature type
Options: point, line, boundary, centroid
Default: point,line,boundary,centroid
tool=string [required]
Options: create, add, delete, copy, move, flip, catadd, catdel, merge, break, snap, connect, extend, extendstart, extendend, chtype, vertexadd, vertexdel, vertexmove, areadel, zbulk, select
create: Create new (empty) vector map
add: Add new features to existing vector map
delete: Delete selected features from vector map
copy: Copy selected features
move: Move selected features in vector map
flip: Flip direction of selected vector lines
catadd: Set new categories to selected vector features for defined layer
catdel: Delete categories from selected vector features for defined layer
merge: Merge selected vector lines
break: Break/split vector lines
snap: Snap vector features in given threshold
connect: Connect two lines
extend: Extend lines
extendstart: Extend start nodes
extendend: Extend end nodes
chtype: Change feature type (point<->centroid, line<->boundary)
vertexadd: Add new vertex to selected vector lines
vertexdel: Remove vertex from selected vector lines
vertexmove: Move vertex of selected vector lines
areadel: Delete selected areas from vector map (based on selected centroids)
zbulk: Z bulk-labeling (automated assignment of z coordinate to vector lines)
select: Select lines and print their ID's
Name of file containing data in GRASS ASCII vector format
'-' for standard input
Difference in x,y,z direction for moving feature or vertex
Threshold distance (coords,snap,query)
'-1' for threshold based on the current resolution settings
Default: -1,0,0
Feature ids
Example: 1,3,7-9,13
Category values
Example: 1,3,7-9,13
List of point coordinates
Bounding box for selecting features
Polygon for selecting features
WHERE conditions of SQL statement without 'where' keyword
Example: income < 1000 and population >= 10000
Query tool
For 'shorter' use negative threshold value, positive value for 'longer'
Options: length, dangle
length: Select only lines or boundaries shorter/longer than threshold distance
dangle: Select dangles shorter/longer than threshold distance
Name of background vector map(s)
Snap added or modified features in the given threshold to the nearest existing feature
Options: no, node, vertex
Default: no
no: Not apply snapping
node: Snap only to node
vertex: Allow snapping also to vertex
Starting value and step for z bulk-labeling
Pair: value,step (e.g. 1100,10)

Table of contents


The module v.edit allows the user to edit a vector map via command line interface.

v.edit supports only "simple" vector features: points, centroids, lines and boundaries. Currently, only 2D vector features (except of tool=zbulk) are supported.

Provides editing features' geometry. Attribute data connected to the vector map are not modified at all.

Vector features can be selected either by internal id, category number cats, coordinates coords, bounding box bbox, polygon, where statement (attribute data) or by query. Selecting features by coordinates is affected by the current 2D resolution or by the threshold distance given by threshold. The options are orthogonal, i.e. can be used in various combinations. For example:

v.edit map=roads tool=select \
  coord=599505,4921010,603389.0625,4918292.1875 \
  threshold=10000 where="label='interstate'"
selects all features (and prints their id's to standard output) covered by two bounding boxes (center at 599505,4921010 and 603389.0625,4918292.1875, size 2*10000) with attribute label='interstate'.


If no vector features are selected or the flag -b is used, topology is not build at the end.


Feature selection

Vector features can be selected in several ways: Additional parameters for vector feature specification are:

Tool description


Create new vector map

Create new (empty) vector map:
v.edit tool=create map=vectmap
Create new vector map and read data from file 'roads.txt':
v.out.ascii in=roads format=standard > roads.txt;
v.edit tool=create map=vectmap input=roads.txt
or alternatively
cat roads.txt | v.edit tool=create map=vectmap input=-

Add new features to existing vector map

Add a new point to the vector map (without header):
echo "P 1 1
 640794 214874
 1 1" | v.edit -n tool=add map=vectmap input=-

# insert new row for each category in attribute table if doesn't exist yet map=vectmap option=cat
The input must be in GRASS ASCII vector format.

Add new features read from standard input:

v.out.ascii in=railroads format=standard | v.edit tool=add map=vectmap input=-

Delete selected features from vector map layer

Remove all vector features with category number 1 or 2:
v.edit tool=delete map=roads cats=1,2
Remove all vector features except of those with category number 1 or 2 (reverse selection):
v.edit -r tool=delete map=roads cats=1,2
Remove features with category 1 or 2 located on coordinates 600952.625,4926107 (bounding box based on the current 2D resolution):
g.region -d;
v.edit tool=delete map=roads cats=1,2 coords=600952.625,4926107
Remove all features with category 1 and 2 covered by two bounding boxes (center coordinates 592542.892,4924766.996 and 603389.062,4918292.187, size 1000 map units):
v.edit map=roads tool=delete \
  coord=592542.892,4924766.996,603389.062,4918292.187 \
  threshold=1000 cat=1,2

Copy selected features from background map

Copy all features with category number 1 from background map:
v.edit map=roads tool=copy bgmap=archsites cat=1

Move features

Move feature (vector point) located on coordinates 602580,4918480 to coordinates 603580,4919480:
v.edit tool=move map=archsites coord=602580,4918480 th=1e-2 move=1000,1000
Move all features with category 1 1000 map units to the west and 1000 map units to the south. Moved features snap to nodes in threshold distance 10 map units:
v.edit tool=move map=roads cat=1 move=1000,-1000 snap=node threshold=-1,10
Move all features defined by bounding box 601530,4921560,602520,4922310 (W,S,E,N) 1000 map units to the east and 1000 map units to the north:
v.edit tool=move map=roads bbox=601530,4921560,602520,4922310 move=-1000,1000

Flip direction of vector lines

Flip direction of all vector lines:
v.edit tool=flip map=streams cats=1-9999 type=line

Add / delete layer category number

Add new layer/category 2/1, 2/3, 2/4, 2/5 to features covered by given polygon:
v.edit tool=catadd map=roads \
  polygon=599877.75,4925088.375,597164.812,4922524.5,601338.562,4920914.625 \
  layer=2 cat=1,3-5
Delete layer/category 1/1, line id 1:
v.edit tool=catdel map=roads id=1 cats=5

Merge lines

Merge two lines with given category number:
v.edit map=roads tool=merge cat=4

Split line on given point

Split line id 810 on coordinates 604268,4923570 in threshold 50 map units:
v.edit map=roads tool=break coords=604268,4923570 id=810 threshold=50

Break selected lines at each intersection

Break selected lines (with category number 1) at each intersection:
v.edit map=roads tool=break cat=1

Snap lines

Snap all lines using threshold distance 20 map units:
v.edit map=roads id=1-9999 tool=snap threshold=-1,20 type=line

Connect lines

Connect line id 48 to line id 565:
v.edit map=roads tool=connect id=48,565
Connect line id 48 to line id 565; line id 60 to line id 50. Maximum threshold distance is 700 map units:
v.edit map=roads tool=connect id=48,565,60,50 threshold=-1,700

Add vertex

Add new vertex to the line located at 600952,4926107, threshold is set to 1 map unit:
v.edit tool=vertexadd map=roads coords=600952,4926107 threshold=1

Delete vertices

Delete vertex located at 593191.608,4925684.849 (threshold set to 0.1 map units). Modify only lines with category 1:
v.edit tool=vertexdel map=roads coord=593191.608,4925684.849 \
  threshold=1-e1 cats=1

Move vertices

Move vertices located at 604441,4921088 (threshold set to 100 map units). Modify only lines with categories 1-10:
v.edit tool=vertexmove map=roads cats=1-10 coord=604441,4921088 \
  threshold=100 move=1000,1000

Select features and print their id's

Print id's of selected features, e.g.:
v.edit map=soils@PERMANENT tool=select \
  bbox=595733.8125,4919781.75,598536.1875,4917396.75 --q
Example with d.vect:
d.vect roads;
d.vect -i map=roads cats=`v.edit map=roads tool=select \
  coord=592542.89243878,4924766.99622811,603389.0625,4918292.1875 \
  threshold=1000 --q` col=red
Select all lines shorter (or equal) than 10 map units:
v.edit map=roads tool=select query=length threshold=-1,0,-10
Select from given bounding box all lines longer then 200 map units:
v.edit map=roads tool=select bbox=598260,4919730,605100,4926240 query=length threshold=-1,0,200

Fix height of contours

Input vector map contains 2D lines representing contours. Height can be assign to the contours using tool=zbulk. First of all 2D lines need to be converted to 3D lines:
v.extrude input=line2 output=line3 height=0 type=line
All lines which intersect with the line given by coordinates will be modified. First found line will get height 1000 map units, height of other selected lines will be increased by 10 map units.
v.edit a2 tool=zbulk bbox=586121.25049368,4911970.21547109,603092.60466035,4927071.25713776 \

SEE ALSO,,,, v.clean, v.extrude, v.split

See also wxGUI vector digitizer.


Original author: Wolf Bergenheim - independent developer
Initial updates: Jachym Cepicky, Mendel University of Agriculture and Forestry in Brno, Czech Republic
Major update by Martin Landa, FBK-irst (formerly ITC-irst), Trento, Italy
Extend tools by Huidae Cho


Available at: v.edit source code (history)

Latest change: Thursday Feb 03 11:10:06 2022 in commit: 547ff44e6aecfb4c9cbf6a4717fc14e521bec0be

Note: This document is for an older version of GRASS GIS that will be discontinued soon. You should upgrade, and read the current manual page.

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