Re: [Geotools-gt2-users] Again: Problem with UTM when NOT forcing switch of axis. Any explanations?

[Martin D. <mar...@ge...>]

Hello Erich

Setting the "force xy axis order" property to "false" doesn't means that the 
order will be (y,x) or (latitude,longitude). It means that the axis order will 
be the one defined by the authority (EPSG in our case). It may be any axis order 
on a CRS-by-CRS basis.

In your case, EPSG:31466 is defined in the EPSG database with (y,x) axis order 
while EPSG:23032 is defined in the database with (x,y) axis order. They are 
defined that way because this is the way they are used by the geographer in 
their country. GeoTools tries to respect what the authority said.

You can see the axis order if you perform a System.out.println(crs). In the 
first case I get:

PROJCS["DHDN / Gauss-Kruger zone 2",
   [...snip...]
   UNIT["m", 1.0],
   AXIS["Northing", NORTH],
   AXIS["Easting", EAST],
   AUTHORITY["EPSG","31466"]]

Note the "Northing", "Easting" axis at the end of this dump. In the second case 
I get:

PROJCS["ED50 / UTM zone 32N",
   [...snip...]
   UNIT["m", 1.0],
   AXIS["Easting", EAST],
   AXIS["Northing", NORTH],
   AUTHORITY["EPSG","23032"]]

Note the "Easting", "Northin" axis at the end of this dump.

You can fetch this information programmatically by invoking 
crs.getCoordinateSystem(), then cs.getAxis(i) and looking at the axis direction.

	Martin