GIS Class - Mike McAdams

SDTS Crash Course

This standard came about through the Federal Information Processing Standard # 173. It is a National standard for data exchange used by U.S. Federal agencies to make data available to state and local governments as well as the general community. It was designed to transfer databases between different computing systems while preserving meanting and minimizing the need for external information describing the data. (ESRI - Arc/Info Help - Located under SDTS in the Index)
"SDTS is a large starndard composed of smaller, more limited subsets that are federally approved as part of the SDTS FIPS 173 standard. These subsets are called profiles. The Topological Vector Profile designed specifiacally for vector data with topology is the only profile supported by SDTSIMPORT." (ESRI - Arc/Info Help - Located under: Master Contents/Command Refrences/ARC/ Commands/SDTSINPORT)

How do you know if you have this data structure?? Well the first four letters in all the files are exactlly the same. In addition they normally have a ".DDF" extention. I'm not sure if all data will be in this form but for now 1:100,000 DLG's come in SDTS compressed format.

Take a look at my stuff:

Arc Usage for SDTS in ArcInfo:
Usage: SDTSIMPORT (in_transfer_prefix) (out_cover) {out_point_cover}


{layer_name} {DD | DROP_DD}

(in_transfer_prefix)
a four character prefix common to all files in the SDTS transfer. The prefix may include a pathname to a directory. If no directory pathname is given the files in the transfer will be read from the current work space.

(out_cover)
is the name of the ARC/INFO polygon coverage that will be created.

Here is an example of what happens when you want to make the above files into coverage.

That is what it should look like. And the data from it is put into a folder named idroads. Projection parameters are usually contained within the data structure. If you do a describe and you don't find what you want then you should look in the *XREF.DDF file.

On to ARC Commands

(c) Copyright Mike McAdams, 1997
if you want something e-mail me at:
mcadams@mail.utexas.edu