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I have a CSV with many points and attributes that I'm trying to convert into a shapefile but I'm having no luck. I have installed gdal-bin and can use my terminal environment to create a shapefile with ogr2ogr, but I'm not getting the desired outcome. I'm running the following:

ogr2ogr -f "ESRI Shapefile" 5_2834k2-25_FAST.shp 5_2834K2-25_DataCompiled_K2.csv -progress -skipfailures -a_srs EPSG:4326 -nlt POINT

And I get:

"5_2834k2-25_FAST.prj" 1 KB
"5_2834k2-25_FAST.shp" 8 KB
"5_2834k2-25_FAST.shx" 6 KB
"5_2834k2-25_FAST.dbf" 7,625 KB

but despite having all my objects and all the features, my SHP has no geometry. It's extent is 0 and recalculating gives me NaN errors in Arc. Now my source CSV does have a lat and lon column (two separate columns) and I've tried to glean from other answers how to get ogr2ogr to see and interpret these values but I cannot.

For example, perhaps using this bit of sqlite to choose the columns:

-dialect sqlite -sql "SELECT easting_col as long, northing_col as lat, geometry FROM input"

and "SELECT lon as long [...]" from input where input is my CSV... but nope. I tried a two-step cheat, thinking I could provide the dbf or shp from the incomplete output of the first as that input in the second but no...

I've tried as well GEOMETRY=AS_XY and I'm reading the man pages, the --long-usage help file as well as the GDAL ogr2ogr page but I just can't come up with the proper syntax.

How can I do this? I'm very frustrated because my columns don't have elaborate names ('Lat' and 'Lon') so I figured it would be very straightforward.

  • 1
    Could you add the column names and one row of data? You can use some fake data if your own are confidential. – user30184 Nov 26 '18 at 6:43
  • You might need to put up a csvt file to tell GDAL which columns to take as geometry. An extract of your csv data (with header) might help. – AndreJ Nov 26 '18 at 7:16
  • you definetely need to tell GDAL how to construct your points; there is no auto-detection of arbitrary numbers as geometries. Try with "SELECT *, MakePoint(<e_col>, <n_col>) AS geometry FROM <input>" (from the CSV). – ThingumaBob Nov 26 '18 at 9:45
  • There is a limited auto-recognition as documented in gdal.org/drv_csv.html Starting with GDAL 2.1, accordingly with the GeoCSV specification, the "CoordX" or "Point(X)" type can be used to specify a column with longitude/easting values, "CoordY" or "Point(Y)" for latitude/northing values and "WKT" for geometries encoded in WKT. Other also documented alternatives are to tell X and Y fields with open options of to write a VRT file that takes care of mapping. – user30184 Nov 26 '18 at 9:56
  • Thanks for all the replies. @user30184 There is a lot of data but here is the first row and a few columns: IDRndX latLonKey Lat Lon nomCat 1966-08-17_DS1036 1966-08-17_DS1037 1972-09-21_Landsat1 2001 -9.44507 -60.7239 Forest F F F latLonKey Lat is sometimes empty. it is the lat multiplied by the lon, nothing fancy. I definitely got the impression there was some auto detection of geometry @ThingumaBob, and I was trying to fulfill those requirements but obviously falling short. I'll look into a cvst file for sure, since my layout should be fairly static, thanks @AndreJ. – Pictory Nov 26 '18 at 19:10
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Success! ogr2ogr -f "ESRI Shapefile" 5_2834k2-25_FAST.shp 5_2834K2-25_DataCompiled_K2.csv -oo X_POSSIBLE_NAMES=lon* -oo Y_POSSIBLE_NAMES=lat* -a_srs EPSG:4326 -nlt POINT -skipfailures

Referring to https://www.gdal.org/drv_csv.html was the key, for me. I found the examples and language on that page more useful than https://www.gdal.org/ogr2ogr.html.

-oo NAME=VALUE: Input dataset open option (format specific)

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