shapefile transform

[Ed McNierney]

David -

That conversion isn't quite on the mark, but could this be a discrepancy
between a U. S. Survey Foot State Plane definition and an International
Foot definition?  It's just about the right size and would be consistent
with 50-year-old data.  If so, you should be able in ArcGIS to edit the
projection definition (I think) to make the adjustment.  That adjustment
would be a factory of 0.999998, though.

        - Ed

Ed McNierney
President and Chief Mapmaker
TopoZone.com / Maps a la carte, Inc.
73 Princeton Street, Suite 305
North Chelmsford, MA  01863
ed at topozone.com
(978) 251-4242  

-----Original Message-----
From: UMN MapServer Users List [mailto:MAPSERVER-USERS at LISTS.UMN.EDU] On
Behalf Of David Bitner
Sent: Wednesday, September 15, 2004 3:49 PM
To: MAPSERVER-USERS at LISTS.UMN.EDU
Subject: [UMN_MAPSERVER-USERS] shapefile transform

Off topic for mapserver list, but could anyone help me figure out a way
to apply a scale transformation to a shapefile.

I have locally surveyed data with the only connection to a "real"
coordinate system being that if you multiply all the coordinates by a
factor of
.9999129 then you get the coordinates in State Plane.  Evidently this is
the result of a mistake made 50 years ago that has been propogated ever
since.

Basically, since there is no projection information for this data and it
is change in scale, rather than just an xy shift I am stuck on how to
make the transformation using ArcGIS, OGR, or other tools.

Thanks,
David