Hi,

I am working with PROJ Rel. 4.7.1 and GDAL/OGR from trunk.

testepsg and gdalsrsinfo tell me that the towgs84 values for EPSG:27700

are 375,-111,431,0,0,0,0 whereas cs2cs reports for the same EPSG code:

446.448,-125.157,542.060,0.1502,0.2470,0.8421,-20.4894

Is this expected behaviour?

Hermann

$ testepsg epsg:27700 | grep PROJ.4

PROJ.4 rendering of [epsg:27700] = +proj=tmerc +lat_0=49 +lon_0=-2

+k=0.9996012717 +x_0=400000 +y_0=-100000 +ellps=airy

+towgs84=375,-111,431,0,0,0,0 +units=m +no_defs

$ gdalsrsinfo epsg:27700 | grep PROJ.4

PROJ.4 : '+proj=tmerc +lat_0=49 +lon_0=-2 +k=0.9996012717 +x_0=400000

+y_0=-100000 +ellps=airy +towgs84=375,-111,431,0,0,0,0 +units=m +no_defs '

$ cs2cs -v +init=epsg:27700 +to +proj=latlong +datum=WGS84

# ---- From Coordinate System ----

#Transverse Mercator

# Cyl, Sph&Ell

# +init=epsg:27700 +proj=tmerc +lat_0=49 +lon_0=-2 +k=0.9996012717

+x_0=400000

# +y_0=-100000 +ellps=airy +datum=OSGB36 +units=m +no_defs

# +towgs84=446.448,-125.157,542.060,0.1502,0.2470,0.8421,-20.4894

#--- following specified but NOT used

# +ellps=airy

# ---- To Coordinate System ----

#Lat/long (Geodetic alias)

#

# +proj=latlong +datum=WGS84 +ellps=WGS84 +towgs84=0,0,0

^C

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