Labeling newly digitized area data

[William L. Baker]

Usually there is a problem node somewhere that needs to have arcs
snapped to it.  To find it in a large polygon, I sometimes divide the
polygon in half by digitizing on screen (select "none" when you start
v.digit or change to the mouse later) a temporary arc between two
existing nodes.  Then try to label each half.  The half with the bad
node still won't label, while the other one will.  Then do the same
procedure again in the bad half.  Eventually you can narrow down
the general location of the bad node.  Then zoom in and pan from
node to node until you can see the unsnapped arc.  There's also a
tool somewhere (I forget - in "tools" perhaps) in v.digit that allows you
to click on a node and highlight each arc that is properly snapped to
the node.  This can help too.

Bill Baker
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Subject: Labeling newly digitized area data
Date: Wed, January 03, 1996 7:53AM

We have been having some difficulty labeling newly digitized areas.
Within v.digit, what appear to be closed polygons, cannot be labeled.
"display open area lines" shows that some of the areas are "open"
On close inspection, the areas seem to be snapped correctly.

We have run v.spag, and v.clean on the files, with limited success,
i.e., apon returning to v.digit, some polygons can be labeled.

There aren't any problems with island-type polygons, only on about 1/3
of the more complex series of attached (shared boundary) polygons.

Please respond to gahadish at iastate.edu

Thank you

Gregg Hadish