v.merge <contrib>     GRASS Reference Manual	<contrib> v.merge



NAME
     v.merge - Merges vector map files.
     (SCS GRASS Vector Program)

SYNOPSIS
     v.merge
     v.merge help
     v.merge [-mv] map=name[,name,...]	output=name subj=name

DESCRIPTION
     Program to read the dig_cats file for each named map.  The
     program then compares the category label (NOT the value) to
     the labels in the named subject file. If the label is found
     in the subject file, the corresponding attribute values of
     the map are changed to the subject file category value.
     When all maps are completed a patch operation is performed.
     This program was designed to merge maps for areas that have
     the same category labels, but different category values
     associated with those labels.
     There are two flags for v.merge:

     Flags:

     -m		       Use RAM to hold subject file category
		       values.	This may be faster than the
		       default (use of disc files);  however,
		       memory may not be large enough for all of
		       the subject file.

     -v		       By default, only the name of the mapset
		       processing is sent to standard output.  In
		       verbose mode, the user is given additional
		       information on program operations.

     Parameters:

     map=name,name,... Vector map--source for composite.

     output=name       New name assigned to vector composite map.

     subj=name	       SUBJ file name.

NOTES
     The program v.make.subj can be run prior to using v.merge.
     v.make.subj will read the category labels of each map in its
     list and create a subject file of labels and values.  Users
     may opt to create the subject file by other means if they
     wish.

     v.rmedge must be run on any mapsets in the v.merge list
     prior to issuing the v.merge command.  Common edges will
     need to be removed prior to the v.merge operation.



GRASS 5.0beta6	      GRASS Development Team			1






v.merge <contrib>     GRASS Reference Manual	<contrib> v.merge



SEE ALSO
     v.make.subj, v.rmedge

AUTHOR
     R.L. Glenn, USDA, SCS, NHQ-CGIS


NOTICE
     This program is part of the contrib section of the GRASS
     distribution.  As such, it is externally contributed code
     that has not been examined or tested by the Office of GRASS
     Integration.











































2		      GRASS Development Team	   GRASS 5.0beta6