[GRASSLIST:4221] Re: NAD27 vs NAD83 SDTS files

Eric G. Miller egm2 at jps.net
Mon Aug 5 22:14:55 EDT 2002

On Mon, Aug 05, 2002 at 01:39:22PM -0800, Victor Wren wrote:

> I'd love to know if anybody has encountered this shift, and what was 
> done to correct it.  Incidentally, I encountered the exact same 
> coordinate shift looking at the SDTS files using the V3.7 DLG viewer 
> from the USGS, but NOT with DLGV32 Pro (the later version), so I 
> suspect it's a problem with incompatible SDTS versions (is there a 
> later version of v.in.sdts and r.in.gdal or libgdal.1.1.so)?  I'm using 

Well, it is peculiar.  I suspect the problem is with the SDTS files
themselves.  As a note, r.in.gdal and v.in.sdts use different code
for reading SDTS files.  Also, neither does projection on import.
Perhaps you have a mix of NAD27 and NAD83 quads?  You can examine the
SDTS files with m.sdts.read (see the ****XREF.DDF file; NAS is NAD27,
NAR is NAD83).

Eric G. Miller <egm2 at jps.net>

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