[GRASS5] m.proj Difference?

Glynn Clements glynn.clements at virgin.net
Fri Jun 7 07:43:26 EDT 2002

Jeshua Lacock wrote:

> I entered all of the same projection values as I did before, and when I 
> attempt to convert the same values I converted with Beta 11, I get 
> results in the Y within 0.7 meters, and the X is off by about 510 
> meters. I get similar results with adjacent coordinates being off by a 
> slight amount positively or negatively based on the direction traversed 
> from the first test point.
> All of the coordinates that I converted with Beta 11 are on the money, 
> and I need to convert some more because of a data loss.
> It seems like it must be a datum shift or some slight difference in the 
> ellipsoid parameters.

Unlike earlier versions, the pre4 version of the proj library performs
datum shifts. Ensure that both locations have the correct datum.

Glynn Clements <glynn.clements at virgin.net>

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