[GIS] Convert WKT (or geojson) geometry to numpy array of coordinates

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I am looking for the fastest way to convert WKT or geojson geometry from string to numpy array of coordinates.

Is it possible to do it strictly in Python and without creating geometry object such Shapely shape, OGRGeometry or GEOSGeometry?

Best Answer

Converting GeoJson to numpy array seems to be much easier than trying to convert WKT to numpy array.

import numpy as np
import json

#if your geojson is a string
geoJson = json.load(geoJsonString)

numpy_array = np.array(geoJson['coordinates'])

and back to geojson:

geoJson['coordinates'] = numpy_array.tolist()

#if you are looking for string geojson
geoJsonString = json.dumps(geoJson)

That's all for geojson. Please answer the question if you have a solution for WKT

Related Solutions

[GIS] How to get elem_info array from WKT or JTS Geometry in Java

You can use the com.vividsolutions.jts.io.oracle.ORAWriter constructor. It "translates a JTS Geometry into an Oracle STRUCT representing an MDSYS.GEOMETRY object.". But for this you need an OracleConnection. It's required by that constructor. Using this kind of implementation you don't have to worry how the several attributes from the SDO_GEOMETRY object are constructed.

Another approach is taken by the gt-jdbc-oracle extension from the GeoTools project: although they depended heavely on the JTS library, the ORAWriter isn't used because it needed to introduce a direct dependency on the OJDBC driver (oracle.jdbc.OracleConnection and others) classes.

I think the Oracle Spatial Java API (sdoapi.jar, sdoutl.jar) already have such facilities: read/write from/to WKT/JGeometry. But you will not be able to work with JTSGeometry..I think. This Java API has the same license as Oracle Locator.

[GIS] Convert list of coordinates to OGRGeometry or WKT

do you mean a line geometry?

something like:

    import numpy as np
    from osgeo import ogr

    v=np.array([[[[-10885205.10690245,3525662.26531131],
       [-10885369.01690829,3525374.0741439],
       [-10885424.08206484,3525269.35422813],
       [-10885439.88685361,3525278.66051977],
       [-10885600.07792469,3525092.02164548],
       [-10885623.88512575,3525100.58301066],
       [-10885627.28152936,3525101.52167386],
       [-10885630.67801411,3525102.45679679]]]])
    line=ogr.Geometry(ogr.wkbLineString)
    for i in v[0,0,:]:
        line.AddPoint(i[0],i[1])
    print line.ExportToWkt()

or other examples of working with geometry

depending on the use of the geometry, you might need to use ogr.wkbLineString25D.

Best Answer

Related Solutions

[GIS] How to get elem_info array from WKT or JTS Geometry in Java

[GIS] Convert list of coordinates to OGRGeometry or WKT

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