Provided by: grass-doc_7.6.0-1_all bug


       v.reclass   -  Changes  vector  category  values  for  an existing vector map according to
       results of SQL queries or a value in attribute table column.


       vector, reclassification, attributes


       v.reclass --help
       v.reclass    input=name     [layer=string]      [type=string[,string,...]]     output=name
       [column=name]   [rules=name]   [--overwrite]  [--help]  [--verbose]  [--quiet]  [--ui]

           Allow output files to overwrite existing files

           Print usage summary

           Verbose module output

           Quiet module output

           Force launching GUI dialog

       input=name [required]
           Name of input vector map
           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

       output=name [required]
           Name for output vector map

           The name of the column whose values are to be used as new categories
           The source for the new key column must be type integer or string

           Full path to the reclass rule file


       v.reclass allows user to create a new vector map  based  on  the  reclassification  of  an
       existing  vector  map.  It  also  allows  the  user to change the key column away from the
       default of "cat" with the column option.

       Rules file may contain on each row either pair:
       keyword value
       (separated by space) or comment beginning with ’#’ (hash).   Definition  of  new  category
       begins  with  keyword cat followed by the new category value.  Keyword where specifies SQL
       where condition.


       No table is created for the reclassed map if the column option is used and the column type
       is  integer  (as  the result could contain ambiguities).  If the column option is used and
       the column type is string, a new table is  created  containing  the  newly  generated  cat
       numbers  and  a  single  column  containing  the  unique  string  column values, sorted in
       alphabetical order.

       For dissolving common boundaries, see v.dissolve.


   Example 1: Reclass by rules
       v.reclass input=land output=land_u type=boundary rules=land.rcl
       the rules file contains :
       # land reclass file
       cat 1
       where use = ’E13’ and owner = ’Jara Cimrman’
       cat 2
       where use = ’E14’
       Produces a new vector area map land_u containing boundaries from land with  area  category
       values selected from database by SQL select statement:
       select id from tland where use = ’E13’ and owner = ’Jara Cimrman’ changed to category 1;
       values selected from database by SQL select statement:
       select id from tland where use = ’E14’ changed to category 2.

   Example 2: Reclass by attribute column
       (North Carolina sample dataset)
       v.reclass in=streams out=streams_by_type column=I_vs_P streams_by_type


       No table is created for reclassed layer if rules option is used.


        v.dissolve, v.extract

       GRASS SQL interface


       R.L. Glenn, USDA, SCS, NHQ-CGIS
       from v.reclass to v.db.reclass and later to v.reclass in 5.7 rewritten by Radim Blazek

       Last changed: $Date: 2015-05-11 02:11:34 +0200 (Mon, 11 May 2015) $


       Available at: v.reclass source code (history)

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       © 2003-2019 GRASS Development Team, GRASS GIS 7.6.0 Reference Manual