Question about Viewing DLG files in GRASS

Shaji Sebastian shaji at gandalf.Berkeley.EDU
Tue Jul 26 23:57:15 EDT 1994


I have spent the last two days trying to view DLG files in  GRASS
that I installed on a SUN workstation and I am feeling rather 
frustrated. I would be very obliged if someone knowledgeable 
could tell me what I am doing wrong.

I obtained these DLG files from a USGS ftp site. I created
 a new LOCATION called sanfran and under that a new MAPSET called
PERMANENT. I put the DLG files in a directory called dlg.

Then I used v.import on these files. I answered yes when the 
program asked me whether I wanted to create an attribute file,
and gave it the first name that came into my head. I told
it not to snap nodes. Everything seemed to go well, until....

I started the x0 driver using d.mon. It complained that the 
region was not set and asked me to run g.region. I ran g.region
and changed the region to the values that I found in the header of
the DLG files. This is what the first few lines of the DLG looked
like:




USGS-NMD  DLG DATA - CHARACTER FORMAT - 09-29-87 VERSION
SAN FRANCISCO, CA                        1978,        100000.  F08
                                                            ^@^@^@\0 0 3636
     3     1    10     2 0.25400000000D+01     4     0     4     1
  -0.122007030000000D+09   0.370370300000000D+08   0.000000000000000D+00
   0.000000000000000D+00   0.000000000000000D+00   0.000000000000000D+00
   0.000000000000000D+00   0.000000000000000D+00   0.000000000000000D+00
   0.000000000000000D+00   0.000000000000000D+00   0.000000000000000D+00
   0.000000000000000D+00   0.000000000000000D+00   0.000000000000000D+00
 0.10000000000D+01 0.00000000000D+00 0.00000000000D+00 0.00000000000D+00
SW       37.500000 -122.250000         566295.14  4150401.44
NW       37.750000 -122.250000         566072.83  4178137.43
NE       37.750000 -122.000000         588098.80  4178342.21
SE       37.500000 -122.000000         588392.23  4150606.89
RAILROADS              0   142   142 010    29    29 010   169   169   1
N    1   566295.14  4150401.44           2           0     0
   163    -8


and when I finally finished with  g.region it looked like this:


                              IDENTIFY REGION

           ============================= DEFAULT REGION ========
           |          Default North:37:45N                     |
           |                                                   |
           |           =======  YOUR REGION  =======           |
           |           | NORTH EDGE:37:45N_____    |           |
           |           |                           |           |
 Def. West |WEST EDGE  |                           |EAST EDGE  | Def. East
 122:15W   |122:15W____|                           |122W_______| 122W
           |           | SOUTH EDGE:37:30N_____    |           |
           |           =============================           |
           |                                                   |
           |          Default South:37:30N                     |
           =====================================================
           PROJECTION: 3 (Latitude-Longitude)         ZONE: 0

                   Default   GRID RESOLUTION   Region
                     0:00:06.47482st-West ---   0:00:06.47482
                     0:00:06.47482th-South --   0:00:06.47482


              AFTER COMPLETING ALL ANSWERS, HIT <ESC> TO CONTINUE
                            (OR <Ctrl-C> TO CANCEL)



I saved the above region and then ran d.vect on the file with the
same name as the dlg file I had converted. It ran through merrily
but nothing came up on the X display.

I have since tried various different combinations of the option settings, 
all to no avail.

 It would be immensely helpful if someone could point out the 
(maybe obvious) error I am making.


Thanks again in advance.
Shaji



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