[gdal-dev] A problem with Alaska State Plane Zone 1 and ogr2ogr

[Even Rouault]

Jay,

I've reproduced and fixed your issue. See 
http://trac.osgeo.org/gdal/ticket/5511 for details

An easy workaround is to add " +wktext" at the end of your proj.4 string. This 
will instruct the GDAL SpatialReference engine to keep literaly your proj.4 
string to use it later. Otherwise the original proj.4 is converted into WKT 
and not preserved, so when needed it afterwards, GDAL rebuilds it from WKT.

Best regards,

Even

> Hello,
> 
> Please forgive me if this is the wrong place for this question, but  I am
> trying to use Alaska State Plane Zone 1 with ogr2ogr, and can't seem to get
> it to project the data correctly.  I am probably doing something wrong, but
> can't seem to figure it out.   I am pretty sure that my projection string
> is correct, as the results from proj match what the NGS's online calculator
> gives.
> 
> When I use ogr2ogr like this:
> ogr2ogr -t_srs "+proj=omerc +lat_0=57 +lonc=-133.6666666666667
> +alpha=-36.86989764583333 +k=0.9999 +x_0=5000000 +y_0=-5000000 +no_uoff
> +datum=NAD83 +units=m +no_defs" akzone1.zhp point.84.shp
> 
> On a shapefile with a single point  - POINT (-131.811033901222117
> 55.409950489560302)
> 
> I get:
> POINT (4988757.639998742379248 -5210867.590697132050991)
> 
> What I get from a shape file reprojected with ESRI products is:
> POINT (936203.399999997578561 399658.200000001117587)
> 
> I believe the ESRI result is correct, as it matches the the NGA online
> converter.
> 
> Proj also generates the correct value:
> Jays-MacBook-Air-2:zone1 Jay$ proj +proj=omerc +lat_0=57
> +lonc=-133.6666666666667 +alpha=-36.86989764583333 +k=0.9999 +x_0=5000000
> +y_0=-5000000 +no_uoff +datum=NAD83 +units=m +no_defs
> -131.811033901222117 55.409950489560302
> 936203.40    399658.20
> 
> 
> So, my question is what am I missing to make the results from ogr2ogr match
> up with proj?
> 
> My thanks,
>  -Jay Cable
> 
> Jays-MacBook-Air-2:zone1 Jay$ proj
> Rel. 4.8.0, 6 March 2012
> usage: proj [ -beEfiIlormsStTvVwW [args] ] [ +opts[=arg] ] [ files ]
> 
> Jays-MacBook-Air-2:zone1 Jay$ ogr2ogr --version
> GDAL 1.11.0, released 2014/04/16
> 
> 
> Oh,  the online NGS converter I mentioned:
> http://www.ngs.noaa.gov/cgi-bin/spc_getpc.prl
> 
>  =======================================================
>            Latitude           Longitude      Datum Zone
>  INPUT =   N552435.8217       W1314839.7220  NAD83 5001
>  =======================================================
> 
>   NORTH(Y)    EAST(X)     AREA  CONVERGENCE   SCALE
>   METERS      METERS            DD MM SS.ss
>   ----------- ----------- ----  -----------   ----------
>   399658.198  936203.401  AK 1   1 32 38.22   0.99990159
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> - Jay Cable - jay at alaska.edu - (907)474-1856 -
> - Geographic Information Network of Alaska -  University of Alaska  -

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