digitizing two polygons

Malcolm Williamson malcolm at cast.uark.edu
Tue Jan 27 07:00:00 EST 1998

Hello Sungwon
The arc-node vector model used by GRASS (and Arc/INFO) does not want to 
see "duplicate lines", i.e, two lines directly on top of each other. 
Boundaries between polygons _should_ be shared, so you only want one line.
Hope that helps,
Malcolm D. Williamson - GIS Specialist         E-mail: malcolm at cast.uark.edu
Center for Advanced Spatial Technologies        Phone: (501) 575-6159
Ozark Rm. 12                                      Fax: (501) 575-5218 
University of Arkansas              
Fayetteville, AR 72701                            Web: http://www.cast.uark.edu

On Mon, 26 Jan 1998, Sung-Won Choi wrote:

> Hello!
> I have some questions!
> for example, I have two polygons having a common boundary,
> so I'm gonna digitizing them in Autocad R13.
> As far as I know, I should digitize the common boundary twice to make 
> two polygons.
> Is it true?
> If not, can I get two polygons by digitizing the common boundary just once?
> Thank you in advance!
> Sungwon Choi

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