[GRASS-user] Estimating import time for large data file

Helmut Kudrnovsky hellik at web.de
Sun May 31 14:59:46 PDT 2020


Rich Shepard wrote
> On Sun, 31 May 2020, Helmut Kudrnovsky wrote:
> 
>> is it
>> EPSG:3857 [1] [2]
>> ?
> 
> Helmut,
> 
> I've no idea. This dataset was downloaded from the Oregon Geospatial
> Enterprise Office (clever name, eh?). The introductory page is here:
> <https://www.oregon.gov/geo/Pages/sdlibrary.aspx>.
> 
> Oregon provides data in three projections:
> 
> # Oregon state standard:
> EPSG 2838  NAD83(HARN)
> <http://www.spatialreference.org/ref/epsg/2838/>
> proj4: +proj=lcc +lat_1=46 +lat_2=44.33333333333334
> +lat_0=43.66666666666666 +lon_0=-120.5 +x_0=2500000 +y_0=0 +ellps=GRS80
> +units=m +no_defs
> 
> # Oregon lon/lat in Lambert Conformal Conic:
> EPSG 2992 +proj=lcc +lat_1=43 +lat_2=45.5 +lat_0=41.75 +lon_0=-120.5
> +x_0=399999.9999984 +y_0=0 +ellps=GRS80 +datum=NAD83 +to_meter=0.3048
> +no_defs
> 
> # Oregon lon/lat in WGS84.
> EPSG 4326: +proj=longlat +ellps=WGS84 +datum=WGS84 +no_defs
> 
> I keep all Oregon spatial data using the first projection. But, sometimes
> a
> dataset is in another projection. When I started importing it into
> grass-7.9.dev I set the projection based on the .prj file and didn't see
> the
> EPSG code it represented.

>PROJCS["WGS_1984_Web_Mercator_Auxiliary_Sphere",
>GEOGCS["GCS_WGS_1984",
>DATUM["D_WGS_1984",
>SPHEROID["WGS_1984",6378137.0,298.257223563]],
>PRIMEM["Greenwich",0.0],UNIT["Degree",0.0174532925199433]],
>PROJECTION["Mercator_Auxiliary_Sphere"],  <=
>PARAMETER["False_Easting",0.0],PARAMETER["False_Northing",0.0],
>PARAMETER["Central_Meridian",0.0],PARAMETER["Standard_Parallel_1",0.0],
>PARAMETER["Auxiliary_Sphere_Type",0.0],UNIT["Meter",1.0]]

------------------

C:\>projinfo EPSG:3857
PROJ.4 string:
+proj=merc +a=6378137 +b=6378137 +lat_ts=0 +lon_0=0 +x_0=0 +y_0=0 +k=1
+units=m +nadgrids=@null +wktext +no_defs +type=crs

WKT2:2019 string:
PROJCRS["WGS 84 / Pseudo-Mercator",
    BASEGEOGCRS["WGS 84",
        DATUM["World Geodetic System 1984",
            ELLIPSOID["WGS 84",6378137,298.257223563,
                LENGTHUNIT["metre",1]]],
        PRIMEM["Greenwich",0,
            ANGLEUNIT["degree",0.0174532925199433]],
        ID["EPSG",4326]],
    CONVERSION["Popular Visualisation Pseudo-Mercator",
        METHOD["Popular Visualisation Pseudo Mercator",
            ID["EPSG",1024]],
        PARAMETER["Latitude of natural origin",0,
            ANGLEUNIT["degree",0.0174532925199433],
            ID["EPSG",8801]],
        PARAMETER["Longitude of natural origin",0,
            ANGLEUNIT["degree",0.0174532925199433],
            ID["EPSG",8802]],
        PARAMETER["False easting",0,
            LENGTHUNIT["metre",1],
            ID["EPSG",8806]],
        PARAMETER["False northing",0,
            LENGTHUNIT["metre",1],
            ID["EPSG",8807]]],
    CS[Cartesian,2],
        AXIS["easting (X)",east,
            ORDER[1],
            LENGTHUNIT["metre",1]],
        AXIS["northing (Y)",north,
            ORDER[2],
            LENGTHUNIT["metre",1]],
    USAGE[
        SCOPE["unknown"],
        AREA["World - 85┬░S to 85┬░N"],
        BBOX[-85.06,-180,85.06,180]],
    ID["EPSG",3857]]

------------------

C:\>projinfo EPSG:2838
PROJ.4 string:
+proj=lcc +lat_0=43.6666666666667 +lon_0=-120.5 +lat_1=46
+lat_2=44.3333333333333 +x_0=2500000 +y_0=0 +ellps=GRS80
+towgs84=0,0,0,0,0,0,0 +units=m +no_defs +type=crs

WKT2:2019 string:
PROJCRS["NAD83(HARN) / Oregon North",
    BASEGEOGCRS["NAD83(HARN)",
        DATUM["NAD83 (High Accuracy Reference Network)",
            ELLIPSOID["GRS 1980",6378137,298.257222101,
                LENGTHUNIT["metre",1]]],
        PRIMEM["Greenwich",0,
            ANGLEUNIT["degree",0.0174532925199433]],
        ID["EPSG",4152]],
    CONVERSION["SPCS83 Oregon North zone (meters)",
        METHOD["Lambert Conic Conformal (2SP)",
            ID["EPSG",9802]],
        PARAMETER["Latitude of false origin",43.6666666666667,
            ANGLEUNIT["degree",0.0174532925199433],
            ID["EPSG",8821]],
        PARAMETER["Longitude of false origin",-120.5,
            ANGLEUNIT["degree",0.0174532925199433],
            ID["EPSG",8822]],
        PARAMETER["Latitude of 1st standard parallel",46,
            ANGLEUNIT["degree",0.0174532925199433],
            ID["EPSG",8823]],
        PARAMETER["Latitude of 2nd standard parallel",44.3333333333333,
            ANGLEUNIT["degree",0.0174532925199433],
            ID["EPSG",8824]],
        PARAMETER["Easting at false origin",2500000,
            LENGTHUNIT["metre",1],
            ID["EPSG",8826]],
        PARAMETER["Northing at false origin",0,
            LENGTHUNIT["metre",1],
            ID["EPSG",8827]]],
    CS[Cartesian,2],
        AXIS["easting (X)",east,
            ORDER[1],
            LENGTHUNIT["metre",1]],
        AXIS["northing (Y)",north,
            ORDER[2],
            LENGTHUNIT["metre",1]],
    USAGE[
        SCOPE["unknown"],
        AREA["USA - Oregon - SPCS - N"],
        BBOX[43.95,-124.17,46.26,-116.47]],
    ID["EPSG",2838]]

------------------
C:\>projinfo EPSG:2992
PROJ.4 string:
+proj=lcc +lat_0=41.75 +lon_0=-120.5 +lat_1=43 +lat_2=45.5
+x_0=399999.9999984 +y_0=0 +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=ft
+no_defs +type=crs

WKT2:2019 string:
PROJCRS["NAD83 / Oregon GIC Lambert (ft)",
    BASEGEOGCRS["NAD83",
        DATUM["North American Datum 1983",
            ELLIPSOID["GRS 1980",6378137,298.257222101,
                LENGTHUNIT["metre",1]]],
        PRIMEM["Greenwich",0,
            ANGLEUNIT["degree",0.0174532925199433]],
        ID["EPSG",4269]],
    CONVERSION["Oregon GIC Lambert (International feet)",
        METHOD["Lambert Conic Conformal (2SP)",
            ID["EPSG",9802]],
        PARAMETER["Latitude of false origin",41.75,
            ANGLEUNIT["degree",0.0174532925199433],
            ID["EPSG",8821]],
        PARAMETER["Longitude of false origin",-120.5,
            ANGLEUNIT["degree",0.0174532925199433],
            ID["EPSG",8822]],
        PARAMETER["Latitude of 1st standard parallel",43,
            ANGLEUNIT["degree",0.0174532925199433],
            ID["EPSG",8823]],
        PARAMETER["Latitude of 2nd standard parallel",45.5,
            ANGLEUNIT["degree",0.0174532925199433],
            ID["EPSG",8824]],
        PARAMETER["Easting at false origin",1312335.958,
            LENGTHUNIT["foot",0.3048],
            ID["EPSG",8826]],
        PARAMETER["Northing at false origin",0,
            LENGTHUNIT["foot",0.3048],
            ID["EPSG",8827]]],
    CS[Cartesian,2],
        AXIS["easting (X)",east,
            ORDER[1],
            LENGTHUNIT["foot",0.3048]],
        AXIS["northing (Y)",north,
            ORDER[2],
            LENGTHUNIT["foot",0.3048]],
    USAGE[
        SCOPE["unknown"],
        AREA["USA - Oregon"],
        BBOX[41.98,-124.6,46.26,-116.47]],
    ID["EPSG",2992]]

------------------
C:\>projinfo EPSG:4326
PROJ.4 string:
+proj=longlat +datum=WGS84 +no_defs +type=crs

WKT2:2019 string:
GEOGCRS["WGS 84",
    DATUM["World Geodetic System 1984",
        ELLIPSOID["WGS 84",6378137,298.257223563,
            LENGTHUNIT["metre",1]]],
    PRIMEM["Greenwich",0,
        ANGLEUNIT["degree",0.0174532925199433]],
    CS[ellipsoidal,2],
        AXIS["geodetic latitude (Lat)",north,
            ORDER[1],
            ANGLEUNIT["degree",0.0174532925199433]],
        AXIS["geodetic longitude (Lon)",east,
            ORDER[2],
            ANGLEUNIT["degree",0.0174532925199433]],
    USAGE[
        SCOPE["unknown"],
        AREA["World"],
        BBOX[-90,-180,90,180]],
    ID["EPSG",4326]]

------------------

using your projection info by the nice GDAL's testepsg tool:

D:\testproj>testepsg projinfo_rich.prj
Validate Succeeds.
WKT[projinfo_rich.prj] =
PROJCS["WGS 84 / Pseudo-Mercator",
    GEOGCS["WGS 84",
        DATUM["WGS_1984",
            SPHEROID["WGS 84",6378137,298.257223563,
                AUTHORITY["EPSG","7030"]],
            AUTHORITY["EPSG","6326"]],
        PRIMEM["Greenwich",0],
        UNIT["Degree",0.0174532925199433]],
    PROJECTION["Mercator_1SP"],
    PARAMETER["central_meridian",0],
    PARAMETER["scale_factor",1],
    PARAMETER["false_easting",0],
    PARAMETER["false_northing",0],
    UNIT["metre",1,
        AUTHORITY["EPSG","9001"]],
    AXIS["Easting",EAST],
    AXIS["Northing",NORTH],
    EXTENSION["PROJ4","+proj=merc +a=6378137 +b=6378137 +lat_ts=0 +lon_0=0
+x_0=0 +y_0=0 +k=1 +units=m +nadgrids=@null +wktext +no_defs"]]

Simplified WKT[projinfo_rich.prj] =
PROJCS["WGS 84 / Pseudo-Mercator",
    GEOGCS["WGS 84",
        DATUM["WGS_1984",
            SPHEROID["WGS 84",6378137,298.257223563]],
        PRIMEM["Greenwich",0],
        UNIT["Degree",0.0174532925199433]],
    PROJECTION["Mercator_1SP"],
    PARAMETER["central_meridian",0],
    PARAMETER["scale_factor",1],
    PARAMETER["false_easting",0],
    PARAMETER["false_northing",0],
    UNIT["metre",1]]

Old Style WKT[projinfo_rich.prj] = PROJCS["WGS 84 /
Pseudo-Mercator",GEOGCS["WGS 84",DATUM["WGS_1984",SPHEROID["WGS
84",6378137,298.257223563]],PRIMEM["Greenwich",0],UNIT["Degree",0.0174532925199433]],PROJECTION["Mercator_1SP"],PARAMETER["central_meridian",0],PARAMETER["scale_factor",1],PARAMETER["false_easting",0],PARAMETER["false_northing",0],UNIT["metre",1]]
ESRI'ified WKT[projinfo_rich.prj] =
PROJCS["WGS_1984_Web_Mercator_Auxiliary_Sphere",
    GEOGCS["GCS_WGS_1984",
        DATUM["D_WGS_1984",
            SPHEROID["WGS_1984",6378137.0,298.257223563]],
        PRIMEM["Greenwich",0.0],
        UNIT["Degree",0.0174532925199433]],
    PROJECTION["Mercator_Auxiliary_Sphere"],
    PARAMETER["False_Easting",0.0],
    PARAMETER["False_Northing",0.0],
    PARAMETER["Central_Meridian",0.0],
    PARAMETER["Standard_Parallel_1",0.0],
    PARAMETER["Auxiliary_Sphere_Type",0.0],
    UNIT["Meter",1.0]]
PROJ.4 rendering of [projinfo_rich.prj] = +proj=merc +a=6378137 +b=6378137
+lat_ts=0 +lon_0=0 +x_0=0 +y_0=0 +k=1 +units=m +nadgrids=@null +wktext
+no_defs

-----------

 it seems the projection of your data (+proj=merc) doesn't correpond to the
Enterprise Office's projections you mentioned (+proj=lcc, +proj=lcc,
+proj=longlat)



-----
best regards
Helmut
--
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