Extracting coordinates of points and writing them to the attribute table

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The workflow below describes how coordinates can be extracted from points and how they can be written into the attribute table.

The example is based on a CSV-File:

674065.18600,3367985.59300,25.83
674066.43200,3367982.46800,25.96
674065.99100,3367983.83600,40.24
674065.92600,3367985.70100,26.00

''' '''

Import points

For the import of the CSV-File use v.in.ascii.

v.in.ascii -z input=/path/to/points_map.csv output=points format=point skip=0 x=1 y=2 z=3 cat=0 fs=,

Add attribute table for vector

Through v.db.addtable an attribute table for the points is created.

v.db.addtable map=points_map table=points_map columns="cat integer"

Connect the vector to the attribute table

Use v.db.connect to connect the vector with its corresponding table.

v.db.connect -o map=points_map table=points_map

Add columns

Use v.db.addcol to add the columns to the attribute table.

v.db.addcol map=points columns="x double precision, y double precision, z double precision"

Add coordinates

Use v.to.db to write the coordinates of the points into the attribute table.

v.to.db map=points_map opt=coor columns="x,y,z"

--TimNorwey 14:01, 26 March 2011 (PDT)