geographical accuracy

Mark Overmeer mark at
Wed Feb 21 15:24:25 GMT 2007

* Andy Armstrong (andy at [070221 15:03]:
> On 21 Feb 2007, at 14:43, Graham Seaman wrote:
> >This improves the output but by a tiny amount (typically a change  
> >in the 4th decimal place of the lat/long) which is smaller than the  
> >error.  Do you know what the correct scalefactor  for wgs84 is?  
> >I've tried googling with no results so far...
> I'm not sure what that's doing so I don't know :)
> As an alternative you could try converting the OSGB36 lat/lon to  
> WGS84 using

By far the best way to recalculate coordinates is by using the
proj4 library.  That library has an interface in Geo::Proj4.
You have to figure-out the epsg code for your projection, and then
the destination projection.  Very simple and fast.

       Mark Overmeer MSc                                MARKOV Solutions
       Mark at                          solutions at         

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