[Xastir] Re: ESRI shapefile troubles

[Tom Russo]

On Fri, Oct 08, 2004 at 08:14:59PM -0400, we recorded a bogon-computron collision of the <shadow at dementia.org> flavor, containing:
> On Fri, 8 Oct 2004, Jason Winningham wrote:
> 
> >
> >On Oct 6, 2004, at 12:39 PM, russo at bogodyn.org wrote:
> >
> >> In a similar vein, I also have a simple dbfawk file for the
> >>24kgrid USGS quadrangle shapefile
> >
> >Where can one find a 24k quad in shapefile format?  Is there a USGS 
> >repository I've missed, or is there a reasonable way to convert them?
> 
> the dlgs can be converted. gdal's ogr2ogr should be able to convert any 
> vector format to shapefile. Actually, that's not strictly true, but it's 
> probably close enough

I'm sorry, I was not clear what I meant:  There is a file called "24kgrid"
that gives the outlines of each quad with the USGS name, not the entire
shapefile version of all the USGS data in a quad.  That file's URL is
listed in README.MAPS.  Since in search and rescue work I'm still bound to
paper maps a lot of the time, it still helps to know what quad to pull out
of the map kit just by glancing at the xastir screen.

You *can* download SDTS versions of the various map layers in USGS quads from 
the EROS data center:  http://edc.usgs.gov/geodata/.  Unfortunately, most
of the data that's available for free in SDTS format is old, and to get new
stuff you have to by DLG-O versions of new data from one of the USGS "Data 
Partners."  Sometimes you luck out and there are new files in STDS.

You can convert STDS map layers to shapefile with ogr2ogr or sdts2shp, both
part of gdal.  Gdal can't convert dlg-o, no free converter I've looked at
so far can handle them.  I wound up buying global mapper so I could translate
dlg-o files to shapefiles.   

I have a tiny handful of USGS vector layers on my shape_web website 
<http://www.swcp.com/~russo/shape_web/>, but they're only for the handful of
quads in my immediate area.

-- 
Tom Russo    KM5VY     SAR502  DM64ux         http://www.swcp.com/~russo/
Tijeras, NM  QRPL#1592 K2#398  SOC#236 AHTB#1 http://www.qsl.net/~km5vy/
(1) Ignorance of your profession is best concealed by solemnity and silence,
which pass for profound knowledge upon the generality of mankind.
                -------"Advice to Officers of the British Army", 1783