How does Survex translate between GPS and UK grid?

Olly Betts olly at survex.com
Mon Oct 5 18:25:16 BST 2020


On Fri, Oct 02, 2020 at 07:38:33PM +0000, Graham Mullan wrote:
> I have a similar query. I have a large dataset covering many caves and
> cave entrances. The set has been collated over a number of years, some
> data is in Survex files and some in Therion files. As far as I recall,
> there are three different EPSG co-ordinate systems buried in various
> parts of the data. Crunching the data in Therion produces a properly
> integrated 3d file with everything on it apparently in the right
> places. I need to know what the output co-ordinate system is as I want
> to import the 3d file into a GIS map.

The output coordinate system is whatever you specified in the input data
using "*cs out ..."

As the manual notes:

| If you use "*cs out" more than once, the second and subsequent
| commands are silently ignored - this makes it possible to combine two
| datasets with different "*cs out" settings without having to modify
| either of them.

Cheers,
    Olly



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