Difference between revisions of "GRASS Vector Attributes"

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* string: text label attribute
* string: text label attribute
* cat: vector ID number
* cat: vector ID number (cat: category, saved in both geometry file as well as attribute table)
* integer: integer precision attribute
* double: double precision attribute
* double: double precision attribute
* ...
* coords: vertex coordinates
* coords: vertex coordinates
* dim: number of dimensions (2D, 3D etc)
* dim: number of dimensions (2D, 3D etc)
=== Modification of attributes ===
* '''Graphical editing''' can be done with the [[WxGUI Attribute Table Manager]] and the [[WxGUI Vector Digitizer#Category.2FAttributes_management|WxGUI Vector Digitizer]]
* '''Command line editing''' can be done with {{cmd|v.db.update}} and related modules.
=== Special cases ===
Two categories  (with slash in the middle) can be assigned to a single vector feature in a single layer. This can happen e.g. when importing overlapping polygons:
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=== See also ===
* [[Vector Attribute Display]]
* [[Vector Database Management]]
* [[Vector map attribute transfer between connected tables]]
* [[Extracting coordinates of points and writing them to the attribute table]]
[[Category:FAQ]]
[[Category:Vector]]

Latest revision as of 21:40, 24 March 2014

Q: How to edit GRASS Attributes?

A: Some commands allow specification of attributes, shown as: attr=string|cat|double|coords|dim

The meanings of these terms:

  • string: text label attribute
  • cat: vector ID number (cat: category, saved in both geometry file as well as attribute table)
  • integer: integer precision attribute
  • double: double precision attribute
  • ...
  • coords: vertex coordinates
  • dim: number of dimensions (2D, 3D etc)

Modification of attributes

Special cases

Two categories (with slash in the middle) can be assigned to a single vector feature in a single layer. This can happen e.g. when importing overlapping polygons:

91/230
73/99
196

See also