On Tue, Aug 29, 2017 at 2:13 PM, Stas Malyshev <smalyshev(a)wikimedia.org> wrote:
[...] Would four decimals
after the dot be enough? According to [4] this is what commercial GPS
device can provide. If not, why and which accuracy would be appropriate?
I think that should be 5 decimals for commercial GPS, per that link?
It also suggests that "The sixth decimal place is worth up to 0.11 m:
you can use this for laying out structures in detail, for designing
landscapes, building roads. It should be more than good enough for
tracking movements of glaciers and rivers. This can be achieved by
taking painstaking measures with GPS, such as differentially corrected
GPS."
Do we hope to store datasets around glacier movement? It seems
possible. (We don't seem to currently
https://www.wikidata.org/wiki/Q770424 )
I skimmed a few search results, and found 7 (or 15) decimals given in
one standard, but the details are beyond my understanding:
http://resources.esri.com/help/9.3/arcgisengine/java/gp_toolref/geoprocessi…
https://stackoverflow.com/questions/1947481/how-many-significant-digits-sho…
https://stackoverflow.com/questions/7167604/how-accurately-should-i-store-l…
--
Nick Wilson (Quiddity)
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