[GRASSLIST:2325] Re: m.proj2

Thu Jan 22 07:40:10 EST 2004

On Thu, Jan 22, 2004 at 11:35:21AM +0000, Paul Kelly wrote:
> On Thu, 22 Jan 2004, Markus Neteler wrote:
> 
> > On Wed, Jan 21, 2004 at 02:10:38PM +0100, Ivan Marchesini wrote:
> > > Dear Users,
> > > I'm trying to use m.proj2 to translate a point from latlong ed50 coord sistem
> > > to the italian sistem (gaus-boaga, rome40)
> > > I have some difficulties to write the sintax of the command....
> > > thank you...
> >
> > With 'cs2cs' (provided by PROJ4) it should be:
> > LATLONG/ED50 -> Gauss-boaga Ovest/Roma40
> >
> > cat coordsED50.txt | cs2cs +init=epsg:4230 +to +init=epsg:26591 \
> >       +towgs84=-85.88,-28.85,+49.67,-1.003,-2.383,-1.808,-27.82 > coordsGB1.txt
> >
> > Fuso Est:
> >  Gauss-boaga Est is +to +init=epsg:26592
> >
> > Be sure to pick the right (local) towgs84 parameters.
> >
> 
> Hello Markus
> Were you able to find towgs84 parameters for eur50 in Italy? I didn't
> reply to this yesterday as I couldn't find any and thought you might know.

I picked them up here:

http://remotesensing.org/lists/proj_archive/msg00484.html

> I would put them into the GRASS datumtransform.table if I knew. The
> NIMA document only seems to have some for Sardinia and Sicily but not
> mainland Italy.
> At least the general ones for europe should be put in in the command line
> above(or does epsg:4230 already contain these?)

No, unfortunately not (Frank W. told me that PROJ4 needs modifications
to handle multiple datums per line (e.g. Zone 1 and 2 in Italy with
Sardinia, Sicily and mainland Italy).

I have a working copy of 'epsg_v64' in SQL (PostgreSQL), they
kindly provided me in a personal mail with complex SQL routines
to extract datums from EPSG. Find attached the result for Italy
in CSV format.

This indicates that all datum transform parameters are available
in EPSG 6.4, but not present in PROJ4, see also:

http://bugzilla.remotesensing.org/show_bug.cgi?id=422

Looking at attached CSV file, you see, that the datum parameters
differs from what I posted - above version is the local datum
of Trieste, while I have attached now the general Italian
mainland values.

Maybe attached values should go into GRASS.

> Also I have a slight suspicion that the ordering of latlong / longlat
> co-ordinates might be different between m.proj2 and cs2cs. It would be worth
> somebody confirming this anyway.

Possibly - no idea.

Markus

PS: Here the SQL query to extract the Italian datums from EPSG 6.4:

SELECT o.coord_op_name, m.coord_op_method_name, p.parameter_name,
pu.sort_order, pv.parameter_value, u.unit_of_meas_name, a.area_name
FROM epsg_coordoperation o
JOIN epsg_coordoperationmethod m
ON m.coord_op_method_code = o.coord_op_method_code
JOIN epsg_coordoperationparamvalue pv
ON pv.coord_op_method_code = o.coord_op_method_code AND
pv.coord_op_code = o.coord_op_code
JOIN epsg_coordoperationparamusage pu
ON pu.coord_op_method_code = o.coord_op_method_Code AND
pu.parameter_code = pv.parameter_code
JOIN epsg_coordoperationparam p
ON p.parameter_code = pv.parameter_code
JOIN epsg_unitofmeasure u
ON u.uom_code = pv.uom_code
JOIN epsg_area a
ON a.area_code = o.area_of_use_code
WHERE o.coord_op_type = 'transformation' AND o.target_crs_code = 4326
AND o.source_crs_code = 4265 AND o.deprecated = 0

-------------- next part --------------
"coord_op_name","coord_op_method_name","parameter_name","sort_order","parameter_value","unit_of_meas_name","area_name"
"Monte Mario to WGS 84 (1)","Geocentric translations","X-axis translation","1","-225","metre","Italy - Sardinia"
"Monte Mario to WGS 84 (1)","Geocentric translations","Y-axis translation","2","-65","metre","Italy - Sardinia"
"Monte Mario to WGS 84 (1)","Geocentric translations","Z-axis translation","3","9","metre","Italy - Sardinia"
"Monte Mario to WGS 84 (4)","Position Vector 7-param. transformation","X-axis translation","1","-104.1","metre","Italy - mainland"
"Monte Mario to WGS 84 (4)","Position Vector 7-param. transformation","Y-axis translation","2","-49.1","metre","Italy - mainland"
"Monte Mario to WGS 84 (4)","Position Vector 7-param. transformation","Z-axis translation","3","-9.9","metre","Italy - mainland"
"Monte Mario to WGS 84 (4)","Position Vector 7-param. transformation","X-axis rotation","4","0.971","arc-second","Italy - mainland"
"Monte Mario to WGS 84 (4)","Position Vector 7-param. transformation","Y-axis rotation","5","-2.917","arc-second","Italy - mainland"
"Monte Mario to WGS 84 (4)","Position Vector 7-param. transformation","Z-axis rotation","6","0.714","arc-second","Italy - mainland"
"Monte Mario to WGS 84 (4)","Position Vector 7-param. transformation","Scale difference","7","-11.68","parts per million","Italy - mainland"
"Monte Mario to WGS 84 (2)","Position Vector 7-param. transformation","X-axis translation","1","-168.6","metre","Italy - Sardinia"
"Monte Mario to WGS 84 (2)","Position Vector 7-param. transformation","Y-axis translation","2","-34","metre","Italy - Sardinia"
"Monte Mario to WGS 84 (2)","Position Vector 7-param. transformation","Z-axis translation","3","38.6","metre","Italy - Sardinia"
"Monte Mario to WGS 84 (2)","Position Vector 7-param. transformation","X-axis rotation","4","-0.374","arc-second","Italy - Sardinia"
"Monte Mario to WGS 84 (2)","Position Vector 7-param. transformation","Y-axis rotation","5","-0.679","arc-second","Italy - Sardinia"
"Monte Mario to WGS 84 (2)","Position Vector 7-param. transformation","Z-axis rotation","6","-1.379","arc-second","Italy - Sardinia"
"Monte Mario to WGS 84 (2)","Position Vector 7-param. transformation","Scale difference","7","-9.48","parts per million","Italy - Sardinia"
"Monte Mario to WGS 84 (3)","Position Vector 7-param. transformation","X-axis translation","1","-50.2","metre","Italy - Sicily"
"Monte Mario to WGS 84 (3)","Position Vector 7-param. transformation","Y-axis translation","2","-50.4","metre","Italy - Sicily"
"Monte Mario to WGS 84 (3)","Position Vector 7-param. transformation","Z-axis translation","3","84.8","metre","Italy - Sicily"
"Monte Mario to WGS 84 (3)","Position Vector 7-param. transformation","X-axis rotation","4","-0.69","arc-second","Italy - Sicily"
"Monte Mario to WGS 84 (3)","Position Vector 7-param. transformation","Y-axis rotation","5","-2.012","arc-second","Italy - Sicily"
"Monte Mario to WGS 84 (3)","Position Vector 7-param. transformation","Z-axis rotation","6","0.459","arc-second","Italy - Sicily"
"Monte Mario to WGS 84 (3)","Position Vector 7-param. transformation","Scale difference","7","-28.08","parts per million","Italy - Sicily"