GRASS GIS (Geographic Resources Analysis Support System)

GRASS 6 Screenshots

Home Intro Docs Download Community Applications Development

User Interface (GUI)

Vector operations

Raster operations

3D and visualization


GRASS 6 Screenshots - Vector Operations

Click image to see larger version

Heads up digitizing with v.digit

Buffering with v.buffer

Overlapping polygons

Overlapping polygons input from Shapefile (or any other OGR simple feature format)

Result (areas colored by number of overlapping areas, categories of layer 1 and 2)

Another example of overlapping features in one layer (overpass)


Example of import and use in GRASS

  • dsn=./shp/ layer=fire output=fire_p
  • v.category input=fire_p output=fire_c type=centroid field=2
  • echo "create table fire_c_2 (id int, num int)" | db.execute
  • v.db.connect map=fire_c driver=pg database=bridge layer=2 table=fire_c_2 key=id
  • map=fire_c layer=2 option=cat col1=id
  • map=fire_c layer=2 qlayer=1 option=query col1=num qcol="count(*)" type=centroid

Number of overlapping features is also written as category to centroid.


Vector overlay using v.overlay


Input A and B


intersection (operator=and)

union (operator=or)


not (operator=not)

exclusive or (operator=xor)

Charting using d.vect.chart

Pie chart

Pie charts (default)

Bar chart

Bar charts (ctype=bar)

Network analysis

Split network into bands using

Allocate subnets using


Shortest path using d.path

© 1997-2005 GRASS Development Team
Imprint | Comments about this page