Internal: Where to find the dimension of DEM in a SDTS file
Anonym
This is some correspondence between Adam B and the USGS about getting dimension info out of SDTS files.
-----Original Message-----
From: Adam Bielecki [SMTP:adam@foreland.Colorado.EDU]
Sent: Friday, June 04, 1999 10:36 AM
To: Adam Bielecki
Subject: SDTS DEMs
---------- Forwarded message ----------
Date: Mon, 19 Oct 1998 14:55:56 -0500
From: George Miller
To: adam@foreland.colorado.edu
Cc: CBrown@usgs.gov, sdts@usgs.gov
Adam;
The information you need is described in the
'The SDTS Mapping of the USGS Digital Elevation Model"
publication @:
ftp://sdts.er.usgs.gov/pub/sdts/datasets/raster/dem/
It is available in Word Perfect and Adobe Acrobat PDF format
(demmap.wp , demmap.pdf)
The information (Table 2.1: Mapping to SDTS Module, Field and Subfield)
is listed in the ID... A16 field --A two-element array containing the number of rows
and columns (m,n) of profiles in the DEM.
The # of row/columns information is contained in the xxxldef.ddf file of the transfer.
SDTS Report
LDEF NROW I 3 472
LDEF NCOL I 3 401
The posting (30 or 10 meter) info is located in the xxxxiref.ddf file
IREF XHRS R 9 30.000000
IREF YHRS R 9 30.000000
y = 472 * 30 = 14160 meters
x = 401 * 30 = 12030 meters
The show173.exe can be used to view the SDTS files.
ftp://sdts.er.usgs.gov/pub/sdts/software/tools/dos/
SHOW173.EXE
If we can be of further assistance, let us know.
George Miller
Computer Specialist
USGS Mid-Continent Mapping Center
Rolla, Mo 65401
gcmiller@usgs.gov
##############################################
In reference to
George,
this person is interested in the number of rows and columns are within a DEM.
Can you answer this one?
Thanks,
Charlie
>>> "Hylan Beydler" 10/19 1:00 PM >>>
From: Adam Bielecki
Date: Fri Oct 16, 12:05pm
To whom it may concern:
Quick question on 7.5 minute DEMs... how do you determine how
many rowsxcolumns in the data? I've read the entire data description,
including the section on type A records, and all the .DDF files that
came with the data, but cannot determine how big the data set is.
Thanks: adam bielecki