Python ogr.OFTInteger() Examples

def create_temp_shape(self, name, point_list):
        vector_file = os.path.join(self.temp_dir.name, name)
        shape_driver = ogr.GetDriverByName("ESRI Shapefile")  # Depreciated; replace at some point
        vector_data_source = shape_driver.CreateDataSource(vector_file)
        vector_layer = vector_data_source.CreateLayer("geometry", self.srs, geom_type=ogr.wkbPolygon)
        ring = ogr.Geometry(ogr.wkbLinearRing)
        for point in point_list:
            ring.AddPoint(point[0], point[1])
        poly = ogr.Geometry(ogr.wkbPolygon)
        poly.AddGeometry(ring)
        vector_feature_definition = vector_layer.GetLayerDefn()
        vector_feature = ogr.Feature(vector_feature_definition)
        vector_feature.SetGeometry(poly)
        vector_layer.CreateFeature(vector_feature)
        vector_layer.CreateField(ogr.FieldDefn("class", ogr.OFTInteger))
        feature = ogr.Feature(vector_layer.GetLayerDefn())
        feature.SetField("class", 3)

        vector_data_source.FlushCache()
        self.vectors.append(vector_data_source)  # Check this is the right thing to be saving here
        self.vector_paths.append(vector_file) 

def create_100x100_shp(self, name):
        """Cretes  a shapefile with a vector layer named "geometry" containing a 100mx100m square , top left corner
        being at wgs coords 10,10.
        This polygon has a field, 'class' with a value of 3. Left in for back-compatability"""
        # TODO Generalise this
        vector_file = os.path.join(self.temp_dir.name, name)
        shape_driver = ogr.GetDriverByName("ESRI Shapefile")  # Depreciated; replace at some point
        vector_data_source = shape_driver.CreateDataSource(vector_file)
        vector_layer = vector_data_source.CreateLayer("geometry", self.srs, geom_type=ogr.wkbPolygon)
        ring = ogr.Geometry(ogr.wkbLinearRing)
        ring.AddPoint(10.0, 10.0)
        ring.AddPoint(10.0, 110.0)
        ring.AddPoint(110.0, 110.0)
        ring.AddPoint(110.0, 10.0)
        ring.AddPoint(10.0, 10.0)
        poly = ogr.Geometry(ogr.wkbPolygon)
        poly.AddGeometry(ring)
        vector_feature_definition = vector_layer.GetLayerDefn()
        vector_feature = ogr.Feature(vector_feature_definition)
        vector_feature.SetGeometry(poly)
        vector_layer.CreateFeature(vector_feature)
        vector_layer.CreateField(ogr.FieldDefn("class", ogr.OFTInteger))
        feature = ogr.Feature(vector_layer.GetLayerDefn())
        feature.SetField("class", 3)

        vector_data_source.FlushCache()
        self.vectors.append(vector_data_source)  # Check this is the right thing to be saving here
        self.vector_paths.append(vector_file) 

def Add_Field(input_lyr, field_name, ogr_field_type):
    """
    Add a field to a layer using the following ogr field types:
    0 = ogr.OFTInteger
    1 = ogr.OFTIntegerList
    2 = ogr.OFTReal
    3 = ogr.OFTRealList
    4 = ogr.OFTString
    5 = ogr.OFTStringList
    6 = ogr.OFTWideString
    7 = ogr.OFTWideStringList
    8 = ogr.OFTBinary
    9 = ogr.OFTDate
    10 = ogr.OFTTime
    11 = ogr.OFTDateTime
    """

    # List fields
    fields_ls = List_Fields(input_lyr)

    # Check if field exist
    if field_name in fields_ls:
        raise Exception('Field: "{0}" already exists'.format(field_name))

    # Create field
    inp_field = ogr.FieldDefn(field_name, ogr_field_type)
    input_lyr.CreateField(inp_field)

    return inp_field 

def Add_Field(input_lyr, field_name, ogr_field_type):
    """
    Add a field to a layer using the following ogr field types:
    0 = ogr.OFTInteger
    1 = ogr.OFTIntegerList
    2 = ogr.OFTReal
    3 = ogr.OFTRealList
    4 = ogr.OFTString
    5 = ogr.OFTStringList
    6 = ogr.OFTWideString
    7 = ogr.OFTWideStringList
    8 = ogr.OFTBinary
    9 = ogr.OFTDate
    10 = ogr.OFTTime
    11 = ogr.OFTDateTime
    """

    # List fields
    fields_ls = List_Fields(input_lyr)

    # Check if field exist
    if field_name in fields_ls:
        raise Exception('Field: "{0}" already exists'.format(field_name))

    # Create field
    inp_field = ogr.FieldDefn(field_name, ogr_field_type)
    input_lyr.CreateField(inp_field)

    return inp_field 

def dbf_to_df(path):
    """
    Return DataFrame from attributes stored in dBase/xBase format.

    Uses OGR's ESRI Shapefile driver to read records from the file.

    Parameters
    ----------
    path : str
        File path to the dBase/xBase file.

    Returns
    -------
    df : pandas.DataFrame

    """
    import ogr

    # Open the file and collect information on fields.
    dbf = ogr.Open(path)
    table = dbf.GetLayer()
    header = table.GetLayerDefn()
    ncolumns = header.GetFieldCount()
    column_names = [header.GetFieldDefn(i).GetName() for i in range(ncolumns)]
    column_types = [header.GetFieldDefn(i).GetType() for i in range(ncolumns)]

    def read(row, i):
        """Return i-th field of a record."""
        # For performance, use the appropriate field type function.
        fld_type = column_types[i]
        if fld_type == ogr.OFTInteger:
            return row.GetFieldAsInteger(i)
        elif fld_type == ogr.OFTReal:
            return row.GetFieldAsDouble(i)
        elif fld_type == ogr.OFTStringList:
            return row.GetFieldAsStringList(i)
        elif fld_type == ogr.OFTIntegerList:
            return row.GetFieldAsIntegerList(i)
        elif fld_type == ogr.OFTRealList:
            return row.GetFieldAsDoubleList(i)
        else:
            return row.GetFieldAsString(i)

    # Represent records with memory-efficient generators.
    values = lambda row: (read(row, i) for i in range(ncolumns))
    records = (values(row) for row in table)

    df = pd.DataFrame.from_records(records, columns=column_names,
                                   coerce_float=False)
    return df