## NAME

v.select

## DESCRIPTION

v.select allows the user to select features from a vector by features from another one.

## NOTES

Only features with category numbers will be considered. If required the v.category module can be used to add them. Typically boundaries do not need to be given a category number, as an area's attributes are inherited from the centroid. Typically points, lines, and centroids will always want to have a cat number.

e.g. take a road which separates two farms. It is ambiguous as to which farm an attribute that is attached to the road belongs to. The boundary only needs a cat number if it will hold its own attributes, such as road name or pavement form. A centroid in each paddock holds the information with respect to ownership, area, etc.

## EXAMPLES

Extract forest fire points from larger fire map:

    v.select ainput=fire binput=forest output=forest_fire

Extract Italian rivers from VMAP0 watercourses map:

    v.select ainput=watrcrsl_eurnasia_wgs84 binput=italy_area \
             output=watrcrsl_italy operator=overlap

## SEE ALSO

v.category, v.overlay, GRASS SQL interface

## AUTHORS

Radim Blazek

Last changed: $Date: 2008-12-13 18:43:05 +0100 (Sat, 13 Dec 2008) $

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