[GRASSLIST:4999] Map (st99_d00.e00) dangles

[Michael Ash]

I would like to thank Radim Blazek of the GRASS project for
his extraordinary effort in helping me track down a problem
in this map AND for explaining how to assess and fix such
problems in general.

(1) Assessing the problem  
(a) v.support with the err= option  creates a vector map of
inputs that create problems; and 
(b) v.out.ascii on the vector map output by the err= option
permits identification of the lines of data that created
problem; and
(c) v.support on the vector map output by the err= option
above permits visual inspection of the problem.

(2) Fixing the problem: v.rm.dangle removes dangles.

I would also like to thank Charles Dingman of the U.S.
Bureau of the Census for his assistance with this problem.
The support of the U.S. Census, for example, by making .e00
files available, is enormously important to my research and
my ability to pursue it in GRASS, and I am deeply grateful.

Sincerely,

Michael Ash, Assistant Professor 
  of Economics and Public Policy         
Department of Economics and CPPA
University of Massachusetts
Amherst, MA 01003        
Tel 413-545-6329 Fax 413-545-2921
Email mash at econs.umass.edu
http://www-unix.oit.umass.edu/~maash