v.spag <main>	      GRASS Reference Manual	    <main> v.spag



NAME
     v.spag - Process spaghetti-digitized binary vector file.
     (GRASS Vector Program)

SYNOPSIS
     v.spag
     v.spag help
     v.spag [-i] map=name [threshold=value]

DESCRIPTION
     This program will fix vector data that were not digitized in
     correct GRASS vector format.  It will create a node at every
     line crossing, and will delete all hanging lines of length
     less than the specified threshold.

COMMAND LINE OPTIONS
     Parameters:

     -i		       Only do Identical line removal pass.

     map=name	       Name of the binary vector file to be
		       fixed.

     threshold=value   Node-snapping threshold value.

NOTES
     The user must run v.support after running v.spag to correct
     the topology (dig_plus) file.

     v.spag generally deletes many lines from the input vector
     map layer.	 Because deleted lines are not eliminated from a
     vector data (dig) file, but are only marked as deleted, the
     user will probably wish to run v.clean on the vector file
     after running v.spag to eliminate any deleted lines from the
     dig file and decrease its size.

BUGS
     This program contains several known bugs.	It will sometimes
     get stuck in a loop in which it creates the same line over
     and over again.  It will occasionally create an incorrect
     line.  Users are strongly urged to back-up their vector data
     files before running this alpha version of v.spag.

     Update Note 1/93:	For GRASS Release 4.1, the -i flag has
     been added and bugs fixed.	 It works better than the 4.0
     release.

SEE ALSO
     v.clean, v.digit, v.support

AUTHOR
     Dave Gerdes,  U.S. Army Construction Engineering Research



GRASS 5.0beta6	      GRASS Development Team			1






v.spag <main>	      GRASS Reference Manual	    <main> v.spag



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2		      GRASS Development Team	   GRASS 5.0beta6