[GRASSLIST:3495] Re: NMEA log to GRASS vector?

[Glynn Clements]

James Cameron wrote:

> m.datum.shift certainly suggests datum shift or transformation is
> possible.  I couldn't find much in that program, so I presume it is
> a feature of the underlying Grass libraries.

The datum shifting functions are part of the "coorcnv" library. 
However, these functions are only used by m.datum.shift (which
transforms individual coordinates) and s.datum.shift (which transforms
site maps). The *.proj programs don't handle datum shifts.

You could use m.datum.shift to transform a set of coordinates (e.g. 
the four corners of the region), then use the results to drive
v.transform.

-- 
Glynn Clements <glynn.clements at virgin.net>