[GRASS-dev] [GRASS GIS] #2456: read CSV from GDAL data directory

GDAL · March 25, 2016, 8:27am

#2456: read CSV from GDAL data directory
---------------------------------+---------------------------------
  Reporter: martinl | Owner: grass-dev@…
      Type: task | Status: new
  Priority: blocker | Milestone: 7.1.0
Component: Projections/Datums | Version: svn-releasebranch70
Resolution: | Keywords: gdal
       CPU: Unspecified | Platform: Unspecified
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Comment (by neteler):

The current state of relbranch70 is:

{{{
GRASS 7.0.4svn (latlong):> g.proj epsg=5514 -w
PROJCS["S-JTSK / Krovak East North",
     GEOGCS["bessel",
         DATUM["Militar_Geographische_Institut",
             SPHEROID["Bessel_1841",6377397.155,299.1528128]],
         PRIMEM["Ferro",-17.666666666668],
         UNIT["degree",0.0174532925199433]],
     PROJECTION["Krovak"],
     PARAMETER["latitude_of_center",49.5],
     PARAMETER["longitude_of_center",42.5],
     PARAMETER["azimuth",0],
     PARAMETER["pseudo_standard_parallel_1",0],
     PARAMETER["scale_factor",0.9999],
     PARAMETER["false_easting",0],
     PARAMETER["false_northing",0],
     UNIT["Meter",1]]

# ==> wrong.
}}}
When (locally) backporting the CSV fix r68128 I finally obtain the right
relations between projection and datum:

{{{
GRASS 7.0.4svn (latlong):> g.proj epsg=5514 datumtrans=-1 -t -w
---
1
Used in whole S_JTSK region
towgs84=589.000,76.000,480.000
Default 3-Parameter Transformation (May not be optimum for older datums;
use this only if no more appropriate options are available.)
---
2
Used in Czech Republic
towgs84=570.8,85.7,462.8,4.998,1.587,5.261,3.56
Accuracy about 1m
---
3
Used in Czech Republic
towgs84=572.213,85.334,461.94,-4.9732,-1.529,-5.2484,3.5378
Accuracy about 1m
---
4
Used in Slovakia
towgs84=485,169.5,483.8,7.786,4.398,4.103,0
Accuracy about 1m

#####
# selecting the 3rd datum:
GRASS 7.0.4svn (latlong):> g.proj epsg=5514 datumtrans=3 -t -w
PROJCS["S-JTSK / Krovak East North",
     GEOGCS["bessel",
         DATUM["System_Jednotne_Trigonometricke_Site_Katastralni",
             SPHEROID["Bessel_1841",6377397.155,299.1528128],
             TOWGS84[589,76,480,0,0,0,0]],
         PRIMEM["Greenwich",0],
         UNIT["degree",0.0174532925199433]],
     PROJECTION["Krovak"],
     PARAMETER["latitude_of_center",49.5],
     PARAMETER["longitude_of_center",24.83333333333333],
     PARAMETER["azimuth",0],
     PARAMETER["pseudo_standard_parallel_1",0],
     PARAMETER["scale_factor",0.9999],
     PARAMETER["false_easting",0],
     PARAMETER["false_northing",0],
     UNIT["Meter",1]]

# ==> better (Greenwich, not Ferro) but azimuth and
pseudo_standard_parallel_1 seem to be wrong.
}}}