[GRASSLIST:2173] Re: Large scale data from US Census

[Rich Shepard]

On Thu, 26 Jul 2001, William A. Perkins wrote:

> I have gotten TIGER files into GRASS. v.in.tig.basic and v.in.tig.lnmk
> (check spelling) still seem to work for up to 1999 TIGER files (but I
> read somewhere that they did not work for 2000, which I have not
> tried).

Bill,

  I remember reading this, too.

> I warn you though, do not expect the TIGER data to be "high resolution" --
> at least in the eastern Washington counties I've worked with they are not.
> I believe that most of the TIGER layers are based on the USGS 1:100k DLG's
> anyway, and even then something got lost in the conversion.

  Oh. I didn't realize this. I've not worked with TIGER files before.

> TIGER files also have trouble matching up with anything else because
> the Bureau pays no attention to the horizontal datum in their original
> data (and they admit this in their documents).

  Ouch! No wonder the census counts are off by so many people.

> I would go with whatever USGS 1:24k SDTS data sets are available.

  Will do.

Thanks,

Rich

Dr. Richard B. Shepard, President

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