[Proj] cs2cs - specifying UTM zone on command line

Martin Desruisseaux martin.desruisseaux at geomatys.com
Thu Nov 1 07:04:24 EST 2018


Le 01/11/2018 à 12:26, support at mnspoint.com a écrit :

> looks like the following quote is the main reason to avoid the "auto"
> implementations unless the method used for the source material is well
> known:
> "However, it is often convenient or necessary to measure a series of
> locations on a single grid when some are located in two adjacent zones."
Indeed, an inconvenient of Transverse Mercator Zoned Grid System is that
it introduces discontinuities at zone borders, where a distance of one
meter suddenly represents a large change in coordinate values because of
zone change. That may be a reason (I'm just guessing) why some CRS like
EPSG:5649 simulates the grid system with a classical (non-gridded)
Transverse Mercator projection: no discontinuity "surprise" as long as
the CRS is the same. However this is valid only for the immediate
neighbour of the CRS zone.

It may be a case where there is no "fit all" solutions: both have
advantages and inconvenient, which may be why both of them are available
in EPSG database.


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