Extracting Site Data from DLG-3 Files

GRASS GRASS user
1

A colleague in the northeast asked me to relay this question in hopes
of receiveing a quick answer from other GRASS users.

He is trying to import data from an ARC-INFO system via a DLG file.
The DLG has point data in it represented as degenerate lines. He can
read the file and see the point data, and the v.in.dlg program recognizes
the lines and comes back with a message about degenerate lines. The file
also contains 1 line that represents a quadrangle boundary. After
importing the file to GRASS, he only gets the quadrangle boundary and no
point data even as degenerate lines. He know this because when he runs
v.support, it only shows 1 processed line. He is running version 4.0.

What can he do to read in all of the data from the DLG?

Responses to either of us would be appreciated.

David Hoover Jim Wesoloski
Boise, ID Amherst, MA
208-334-1525 413-253-9056
a16dhoover@attmail.com

Thanks in advance !

David Hoover
State GIS Specialist
Idaho Soil Conservation Service

a16dhoover!attmail.com

2

I have imported a topographic map into an xy location. I now want to
rectify this map to UTM coordinates. When I display the topographic map
in the xy location the map looks fine, however after I rectify the topo I
lose almost all of the resolution and contours. I know the problem is
related to the nearest neighbor interpolation after the rotation and the
fact that the contours are defined by very few pixels. I want to use the
topographic map as a base map. Does anyone have any suggestions on how I
could go about doing this?

Thanks,

Melissa Cowoski
Geological and Environmental Sciences
Stanford University