示例#1
0
    def read_from_qgis_native(self, qgis_layer):
        """Read raster data from qgis layer QgsRasterLayer.

            A stub is used now:
                save all data in a file,
                then call safe.read_from_file

            Raises:
                * TypeError         if qgis is not avialable
                * IOError           if can't store temporary file
                * GetDataError      if can't create copy of qgis_layer's
                                        dataProvider
        """
        base_name = unique_filename()
        file_name = base_name + '.tif'

        file_writer = QgsRasterFileWriter(file_name)
        pipe = QgsRasterPipe()
        provider = qgis_layer.dataProvider()
        if not pipe.set(provider.clone()):
            msg = "Cannot set pipe provider"
            raise GetDataError(msg)

        file_writer.writeRaster(
            pipe,
            provider.xSize(),
            provider.ySize(),
            provider.extent(),
            provider.crs())

        # Write keywords if any
        write_keywords(self.keywords, base_name + '.keywords')
        self.read_from_file(file_name)
示例#2
0
    def read_from_qgis_native(self, qgis_layer):
        """Read and unpack vector data from qgis layer QgsVectorLayer.

            A stub is used now:
                save all data in a file,
                then call safe.read_from_file

            Raises:
                * TypeError         if qgis is not avialable
                * IOError           if can't store temporary file
        """
        # FIXME (DK): this branch isn't covered by test
        if not QGIS_IS_AVAILABLE:
            msg = ('Used data is QgsVectorLayer instance, '
                   'but QGIS is not available.')
            raise TypeError(msg)

        base_name = unique_filename()
        file_name = base_name + '.shp'
        error = QgsVectorFileWriter.writeAsVectorFormat(
            qgis_layer,
            file_name,
            "UTF8",
            qgis_layer.crs(),
            "ESRI Shapefile"
        )
        if error != QgsVectorFileWriter.NoError:
            # FIXME (DK): this branch isn't covered by test
            msg = ('Can not save data in temporary file.')
            raise IOError(msg)

        # Write keywords if any
        write_keywords(self.keywords, base_name + '.keywords')
        self.read_from_file(file_name)
示例#3
0
    def read_from_qgis_native(self, qgis_layer):
        """Read raster data from qgis layer QgsRasterLayer.

            A stub is used now:
                save all data in a file,
                then call safe.read_from_file

            Raises:
                * TypeError         if qgis is not avialable
                * IOError           if can't store temporary file
                * GetDataError      if can't create copy of qgis_layer's
                                        dataProvider
        """
        base_name = unique_filename()
        file_name = base_name + '.tif'

        file_writer = QgsRasterFileWriter(file_name)
        pipe = QgsRasterPipe()
        provider = qgis_layer.dataProvider()
        if not pipe.set(provider.clone()):
            msg = "Cannot set pipe provider"
            raise GetDataError(msg)

        file_writer.writeRaster(pipe, provider.xSize(), provider.ySize(),
                                provider.extent(), provider.crs())

        # Write keywords if any
        write_keywords(self.keywords, base_name + '.keywords')
        self.read_from_file(file_name)
示例#4
0
    def read_from_qgis_native(self, qgis_layer):
        """Read and unpack vector data from qgis layer QgsVectorLayer.

            A stub is used now:
                save all data in a file,
                then call safe.read_from_file

            Raises:
                * TypeError         if qgis is not avialable
                * IOError           if can't store temporary file
        """
        # FIXME (DK): this branch isn't covered by test
        if not QGIS_IS_AVAILABLE:
            msg = ('Used data is QgsVectorLayer instance, '
                   'but QGIS is not avialable.')
            raise TypeError(msg)

        base_name = unique_filename()
        file_name = base_name + '.shp'
        error = QgsVectorFileWriter.writeAsVectorFormat(
            qgis_layer,
            file_name,
            "UTF8",
            qgis_layer.crs(),
            "ESRI Shapefile"
        )
        if error != QgsVectorFileWriter.NoError:
            # FIXME (DK): this branch isn't covered by test
            msg = ('Can not save data in temporary file.')
            raise IOError(msg)

        # Write keywords if any
        write_keywords(self.keywords, base_name + '.keywords')
        self.read_from_file(file_name)
示例#5
0
    def write_to_file(self, filename):
        """Save raster data to file

        Args:
            * filename: filename with extension .tif

        Gdal documentation at: http://www.gdal.org/classGDALRasterBand.html
        """

        # Check file format
        basename, extension = os.path.splitext(filename)

        msg = ('Invalid file type for file %s. Only extension '
               'tif allowed.' % filename)
        verify(extension in ['.tif'], msg)
        file_format = DRIVER_MAP[extension]

        # Get raster data
        A = self.get_data()

        # Get Dimensions. Note numpy and Gdal swap order
        N, M = A.shape

        # Create empty file.
        # FIXME (Ole): It appears that this is created as single
        #              precision even though Float64 is specified
        #              - see issue #17
        driver = gdal.GetDriverByName(file_format)
        fid = driver.Create(filename, M, N, 1, gdal.GDT_Float64)
        if fid is None:
            msg = ('Gdal could not create filename %s using '
                   'format %s' % (filename, file_format))
            raise WriteLayerError(msg)

        self.filename = filename

        # Write metada
        fid.SetProjection(str(self.projection))
        fid.SetGeoTransform(self.geotransform)

        # Write data
        fid.GetRasterBand(1).WriteArray(A)
        fid.GetRasterBand(1).SetNoDataValue(self.get_nodata_value())
        fid = None  # Close

        # Write keywords if any
        write_keywords(self.keywords, basename + '.keywords')
示例#6
0
    def write_to_file(self, filename):
        """Save raster data to file

        Args:
            * filename: filename with extension .tif

        Gdal documentation at: http://www.gdal.org/classGDALRasterBand.html
        """

        # Check file format
        basename, extension = os.path.splitext(filename)

        msg = ('Invalid file type for file %s. Only extension '
               'tif allowed.' % filename)
        verify(extension in ['.tif'], msg)
        file_format = DRIVER_MAP[extension]

        # Get raster data
        A = self.get_data()

        # Get Dimensions. Note numpy and Gdal swap order
        N, M = A.shape

        # Create empty file.
        # FIXME (Ole): It appears that this is created as single
        #              precision even though Float64 is specified
        #              - see issue #17
        driver = gdal.GetDriverByName(file_format)
        fid = driver.Create(filename, M, N, 1, gdal.GDT_Float64)
        if fid is None:
            msg = ('Gdal could not create filename %s using '
                   'format %s' % (filename, file_format))
            raise WriteLayerError(msg)

        self.filename = filename

        # Write metada
        fid.SetProjection(str(self.projection))
        fid.SetGeoTransform(self.geotransform)

        # Write data
        fid.GetRasterBand(1).WriteArray(A)
        fid.GetRasterBand(1).SetNoDataValue(self.get_nodata_value())
        fid = None  # Close

        # Write keywords if any
        write_keywords(self.keywords, basename + '.keywords')
示例#7
0
    def write_to_file(self, filename):
        """Save raster data to file

        Input
            filename: filename with extension .tif
        """

        # Check file format
        basename, extension = os.path.splitext(filename)

        msg = ('Invalid file type for file %s. Only extension '
               'tif allowed.' % filename)
        verify(extension in ['.tif', '.asc'], msg)
        format = DRIVER_MAP[extension]

        # Get raster data
        A = self.get_data()

        # Get Dimensions. Note numpy and Gdal swap order
        N, M = A.shape

        # Create empty file.
        # FIXME (Ole): It appears that this is created as single
        #              precision even though Float64 is specified
        #              - see issue #17
        driver = gdal.GetDriverByName(format)
        fid = driver.Create(filename, M, N, 1, gdal.GDT_Float64)
        if fid is None:
            msg = ('Gdal could not create filename %s using '
                   'format %s' % (filename, format))
            raise Exception(msg)

        # Write metada
        fid.SetProjection(str(self.projection))
        fid.SetGeoTransform(self.geotransform)

        # Write data
        fid.GetRasterBand(1).WriteArray(A)

        # Write keywords if any
        write_keywords(self.keywords, basename + '.keywords')
示例#8
0
    def write_to_file(self, filename, sublayer=None):
        """Save vector data to file

        Args:
            * filename: filename with extension .shp or .gml
            * sublayer: Optional string for writing a sublayer. Ignored
                  unless we are writing to an sqlite file.

        Note:
            Shp limitation, if attribute names are longer than 10
            characters they will be truncated. This is due to limitations in
            the shp file driver and has to be done here since gdal v1.7 onwards
            has changed its handling of this issue:
            http://www.gdal.org/ogr/drv_shapefile.html

            **For this reason we recommend writing to spatialite.**

        """

        # Check file format
        basename, extension = os.path.splitext(filename)

        msg = ('Invalid file type for file %s. Only extensions '
               'sqlite, shp or gml allowed.' % filename)
        verify(extension in ['.sqlite', '.shp', '.gml'], msg)
        driver = DRIVER_MAP[extension]

        # FIXME (Ole): Tempory flagging of GML issue (ticket #18)
        if extension == '.gml':
            msg = ('OGR GML driver does not store geospatial reference.'
                   'This format is disabled for the time being. See '
                   'https://github.com/AIFDR/riab/issues/18')
            raise WriteLayerError(msg)

        # Derive layername from filename (excluding preceding dirs)
        if sublayer is None or extension == '.shp':
            layername = os.path.split(basename)[-1]
        else:
            layername = sublayer

        # Get vector data
        if self.is_polygon_data:
            geometry = self.get_geometry(as_geometry_objects=True)
        else:
            geometry = self.get_geometry()
        data = self.get_data()

        N = len(geometry)

        # Clear any previous file of this name (ogr does not overwrite)
        try:
            os.remove(filename)
        except OSError:
            pass

        # Create new file with one layer
        drv = ogr.GetDriverByName(driver)
        if drv is None:
            msg = 'OGR driver %s not available' % driver
            raise WriteLayerError(msg)

        ds = drv.CreateDataSource(filename)
        if ds is None:
            msg = 'Creation of output file %s failed' % filename
            raise WriteLayerError(msg)

        lyr = ds.CreateLayer(layername,
                             self.projection.spatial_reference,
                             self.geometry_type)
        if lyr is None:
            msg = 'Could not create layer %s' % layername
            raise WriteLayerError(msg)

        # Define attributes if any
        store_attributes = False
        fields = []
        if data is not None:
            if len(data) > 0:
                try:
                    fields = data[0].keys()
                except:
                    msg = ('Input parameter "attributes" was specified '
                           'but it does not contain list of dictionaries '
                           'with field information as expected. The first '
                           'element is %s' % data[0])
                    raise WriteLayerError(msg)
                else:
                    # Establish OGR types for each element
                    ogrtypes = {}
                    for name in fields:
                        att = data[0][name]
                        py_type = type(att)
                        msg = ('Unknown type for storing vector '
                               'data: %s, %s' % (name, str(py_type)[1:-1]))
                        verify(py_type in TYPE_MAP, msg)
                        ogrtypes[name] = TYPE_MAP[py_type]

            else:
                #msg = ('Input parameter "data" was specified '
                #       'but appears to be empty')
                #raise InaSAFEError(msg)
                pass

            # Create attribute fields in layer
            store_attributes = True
            for name in fields:
                fd = ogr.FieldDefn(name, ogrtypes[name])
                # FIXME (Ole): Trying to address issue #16
                #              But it doesn't work and
                #              somehow changes the values of MMI in test
                #width = max(128, len(name))
                #print name, width
                #fd.SetWidth(width)

                # Silent handling of warnings like
                # Warning 6: Normalized/laundered field name:
                #'CONTENTS_LOSS_AUD' to 'CONTENTS_L'
                gdal.PushErrorHandler('CPLQuietErrorHandler')
                if lyr.CreateField(fd) != 0:
                    msg = 'Could not create field %s' % name
                    raise WriteLayerError(msg)

                # Restore error handler
                gdal.PopErrorHandler()

        # Store geometry
        geom = ogr.Geometry(self.geometry_type)
        layer_def = lyr.GetLayerDefn()
        for i in range(N):
            # Create new feature instance
            feature = ogr.Feature(layer_def)

            # Store geometry and check
            if self.is_point_data:
                x = float(geometry[i][0])
                y = float(geometry[i][1])
                geom.SetPoint_2D(0, x, y)
            elif self.is_line_data:
                geom = array2line(geometry[i],
                                  geometry_type=ogr.wkbLineString)
            elif self.is_polygon_data:
                # Create polygon geometry
                geom = ogr.Geometry(ogr.wkbPolygon)

                # Add outer ring
                linear_ring = array2line(geometry[i].outer_ring,
                                         geometry_type=ogr.wkbLinearRing)
                geom.AddGeometry(linear_ring)

                # Add inner rings if any
                for A in geometry[i].inner_rings:
                    geom.AddGeometry(array2line(A,
                                     geometry_type=ogr.wkbLinearRing))
            else:
                msg = 'Geometry type %s not implemented' % self.geometry_type
                raise WriteLayerError(msg)

            feature.SetGeometry(geom)

            G = feature.GetGeometryRef()
            if G is None:
                msg = 'Could not create GeometryRef for file %s' % filename
                raise WriteLayerError(msg)

            # Store attributes
            if store_attributes:
                for j, name in enumerate(fields):
                    actual_field_name = layer_def.GetFieldDefn(j).GetNameRef()

                    val = data[i][name]

                    if type(val) == numpy.ndarray:
                        # A singleton of type <type 'numpy.ndarray'> works
                        # for gdal version 1.6 but fails for version 1.8
                        # in SetField with error: NotImplementedError:
                        # Wrong number of arguments for overloaded function
                        val = float(val)
                    elif val is None:
                        val = ''

                    # We do this because there is NaN problem on windows
                    # NaN value must be converted to _pseudo_in to solve the
                    # problem. But, when InaSAFE read the file, it'll be
                    # converted back to NaN value, so that NaN in InaSAFE is a
                    # numpy.nan
                    # please check https://github.com/AIFDR/inasafe/issues/269
                    # for more information
                    if val != val:
                        val = _pseudo_inf

                    feature.SetField(actual_field_name, val)

            # Save this feature
            if lyr.CreateFeature(feature) != 0:
                msg = 'Failed to create feature %i in file %s' % (i, filename)
                raise WriteLayerError(msg)

            feature.Destroy()

        # Write keywords if any
        write_keywords(self.keywords, basename + '.keywords')
示例#9
0
    def write_to_file(self, filename, sublayer=None):
        """Save vector data to file

        :param filename: filename with extension .shp or .gml
        :type filename: str

        :param sublayer: Optional parameter for writing a sublayer. Ignored
            unless we are writing to an sqlite file.
        :type sublayer: str

        :raises: WriteLayerError

        Note:
            Shp limitation, if attribute names are longer than 10
            characters they will be truncated. This is due to limitations in
            the shp file driver and has to be done here since gdal v1.7 onwards
            has changed its handling of this issue:
            http://www.gdal.org/ogr/drv_shapefile.html

            **For this reason we recommend writing to spatialite.**

        """

        # Check file format
        base_name, extension = os.path.splitext(filename)

        msg = ('Invalid file type for file %s. Only extensions '
               'sqlite, shp or gml allowed.' % filename)
        verify(extension in ['.sqlite', '.shp', '.gml'], msg)
        driver = DRIVER_MAP[extension]

        # FIXME (Ole): Tempory flagging of GML issue (ticket #18)
        if extension == '.gml':
            msg = ('OGR GML driver does not store geospatial reference.'
                   'This format is disabled for the time being. See '
                   'https://github.com/AIFDR/riab/issues/18')
            raise WriteLayerError(msg)

        # Derive layer_name from filename (excluding preceding dirs)
        if sublayer is None or extension == '.shp':
            layer_name = os.path.split(base_name)[-1]
        else:
            layer_name = sublayer

        # Get vector data
        if self.is_polygon_data:
            geometry = self.get_geometry(as_geometry_objects=True)
        else:
            geometry = self.get_geometry()
        data = self.get_data()

        N = len(geometry)

        # Clear any previous file of this name (ogr does not overwrite)
        try:
            os.remove(filename)
        except OSError:
            pass

        # Create new file with one layer
        drv = ogr.GetDriverByName(driver)
        if drv is None:
            msg = 'OGR driver %s not available' % driver
            raise WriteLayerError(msg)

        ds = drv.CreateDataSource(filename)
        if ds is None:
            msg = 'Creation of output file %s failed' % filename
            raise WriteLayerError(msg)

        lyr = ds.CreateLayer(layer_name, self.projection.spatial_reference,
                             self.geometry_type)
        if lyr is None:
            msg = 'Could not create layer %s' % layer_name
            raise WriteLayerError(msg)

        # Define attributes if any
        store_attributes = False
        fields = []
        if data is not None:
            if len(data) > 0:
                try:
                    fields = data[0].keys()
                except:
                    msg = ('Input parameter "attributes" was specified '
                           'but it does not contain list of dictionaries '
                           'with field information as expected. The first '
                           'element is %s' % data[0])
                    raise WriteLayerError(msg)
                else:
                    # Establish OGR types for each element
                    ogr_types = {}
                    for name in fields:
                        att = data[0][name]
                        py_type = type(att)
                        msg = ('Unknown type for storing vector '
                               'data: %s, %s' % (name, str(py_type)[1:-1]))
                        verify(py_type in TYPE_MAP, msg)
                        ogr_types[name] = TYPE_MAP[py_type]

            else:
                #msg = ('Input parameter "data" was specified '
                #       'but appears to be empty')
                #raise InaSAFEError(msg)
                pass

            # Create attribute fields in layer
            store_attributes = True
            for name in fields:
                fd = ogr.FieldDefn(name, ogr_types[name])
                # FIXME (Ole): Trying to address issue #16
                #              But it doesn't work and
                #              somehow changes the values of MMI in test
                #width = max(128, len(name))
                #print name, width
                #fd.SetWidth(width)

                # Silent handling of warnings like
                # Warning 6: Normalized/laundered field name:
                #'CONTENTS_LOSS_AUD' to 'CONTENTS_L'
                gdal.PushErrorHandler('CPLQuietErrorHandler')
                if lyr.CreateField(fd) != 0:
                    msg = 'Could not create field %s' % name
                    raise WriteLayerError(msg)

                # Restore error handler
                gdal.PopErrorHandler()

        # Store geometry
        geom = ogr.Geometry(self.geometry_type)
        layer_def = lyr.GetLayerDefn()
        for i in range(N):
            # Create new feature instance
            feature = ogr.Feature(layer_def)

            # Store geometry and check
            if self.is_point_data:
                x = float(geometry[i][0])
                y = float(geometry[i][1])
                geom.SetPoint_2D(0, x, y)
            elif self.is_line_data:
                geom = array_to_line(geometry[i],
                                     geometry_type=ogr.wkbLineString)
            elif self.is_polygon_data:
                # Create polygon geometry
                geom = ogr.Geometry(ogr.wkbPolygon)

                # Add outer ring
                linear_ring = array_to_line(geometry[i].outer_ring,
                                            geometry_type=ogr.wkbLinearRing)
                geom.AddGeometry(linear_ring)

                # Add inner rings if any
                for A in geometry[i].inner_rings:
                    geom.AddGeometry(
                        array_to_line(A, geometry_type=ogr.wkbLinearRing))
            else:
                msg = 'Geometry type %s not implemented' % self.geometry_type
                raise WriteLayerError(msg)

            feature.SetGeometry(geom)

            G = feature.GetGeometryRef()
            if G is None:
                msg = 'Could not create GeometryRef for file %s' % filename
                raise WriteLayerError(msg)

            # Store attributes
            if store_attributes:
                for j, name in enumerate(fields):
                    actual_field_name = layer_def.GetFieldDefn(j).GetNameRef()

                    val = data[i][name]

                    if type(val) == numpy.ndarray:
                        # A singleton of type <type 'numpy.ndarray'> works
                        # for gdal version 1.6 but fails for version 1.8
                        # in SetField with error: NotImplementedError:
                        # Wrong number of arguments for overloaded function
                        val = float(val)
                    elif val is None:
                        val = ''

                    # We do this because there is NaN problem on windows
                    # NaN value must be converted to _pseudo_in to solve the
                    # problem. But, when InaSAFE read the file, it'll be
                    # converted back to NaN value, so that NaN in InaSAFE is a
                    # numpy.nan
                    # please check https://github.com/AIFDR/inasafe/issues/269
                    # for more information
                    if val != val:
                        val = _pseudo_inf

                    feature.SetField(actual_field_name, val)

            # Save this feature
            if lyr.CreateFeature(feature) != 0:
                msg = 'Failed to create feature %i in file %s' % (i, filename)
                raise WriteLayerError(msg)

            feature.Destroy()

        # Write keywords if any
        write_keywords(self.keywords, base_name + '.keywords')
示例#10
0
    def write_to_file(self, filename):
        """Save vector data to file

        Input
            filename: filename with extension .shp or .gml

        Note, if attribute names are longer than 10 characters they will be
        truncated. This is due to limitations in the shp file driver and has
        to be done here since gdal v1.7 onwards has changed its handling of
        this issue: http://www.gdal.org/ogr/drv_shapefile.html
        """

        # Check file format
        basename, extension = os.path.splitext(filename)

        msg = ('Invalid file type for file %s. Only extensions '
               'shp or gml allowed.' % filename)
        assert extension == '.shp' or extension == '.gml', msg
        driver = DRIVER_MAP[extension]

        # FIXME (Ole): Tempory flagging of GML issue (ticket #18)
        if extension == '.gml':
            msg = ('OGR GML driver does not store geospatial reference.'
                   'This format is disabled for the time being. See '
                   'https://github.com/AIFDR/riab/issues/18')
            raise Exception(msg)

        # Derive layername from filename (excluding preceding dirs)
        layername = os.path.split(basename)[-1]

        # Get vector data
        geometry = self.get_geometry()
        data = self.get_data()

        N = len(geometry)

        # Clear any previous file of this name (ogr does not overwrite)
        try:
            os.remove(filename)
        except:
            pass

        # Create new file with one layer
        drv = ogr.GetDriverByName(driver)
        if drv is None:
            msg = 'OGR driver %s not available' % driver
            raise Exception(msg)

        ds = drv.CreateDataSource(filename)
        if ds is None:
            msg = 'Creation of output file %s failed' % filename
            raise Exception(msg)

        lyr = ds.CreateLayer(layername,
                             self.projection.spatial_reference,
                             self.geometry_type)
        if lyr is None:
            msg = 'Could not create layer %s' % layername
            raise Exception(msg)

        # Define attributes if any
        store_attributes = False
        if data is not None:
            if len(data) > 0:
                try:
                    fields = data[0].keys()
                except:
                    msg = ('Input parameter "attributes" was specified '
                           'but it does not contain dictionaries with '
                           'field information as expected. The first'
                           'element is %s' % data[0])
                    raise Exception(msg)
                else:
                    # Establish OGR types for each element
                    ogrtypes = {}
                    for name in fields:
                        att = data[0][name]
                        py_type = type(att)
                        msg = ('Unknown type for storing vector '
                               'data: %s, %s' % (name, str(py_type)[1:-1]))
                        assert py_type in TYPE_MAP, msg
                        ogrtypes[name] = TYPE_MAP[py_type]

            else:
                msg = ('Input parameter "data" was specified '
                       'but appears to be empty')
                raise Exception(msg)

            # Create attribute fields in layer
            store_attributes = True
            for name in fields:
                fd = ogr.FieldDefn(name, ogrtypes[name])
                # FIXME (Ole): Trying to address issue #16
                #              But it doesn't work and
                #              somehow changes the values of MMI in test
                #width = max(128, len(name))
                #print name, width
                #fd.SetWidth(width)

                # Silent handling of warnings like
                # Warning 6: Normalized/laundered field name:
                #'CONTENTS_LOSS_AUD' to 'CONTENTS_L'
                gdal.PushErrorHandler('CPLQuietErrorHandler')
                if lyr.CreateField(fd) != 0:
                    msg = 'Could not create field %s' % name
                    raise Exception(msg)

                # Restore error handler
                gdal.PopErrorHandler()

        # Store geometry
        geom = ogr.Geometry(self.geometry_type)
        layer_def = lyr.GetLayerDefn()
        for i in range(N):
            # Create new feature instance
            feature = ogr.Feature(layer_def)

            # Store geometry and check
            if self.geometry_type == ogr.wkbPoint:
                x = float(geometry[i][0])
                y = float(geometry[i][1])
                geom.SetPoint_2D(0, x, y)
            elif self.geometry_type == ogr.wkbPolygon:
                wkt = array2wkt(geometry[i], geom_type='POLYGON')
                geom = ogr.CreateGeometryFromWkt(wkt)
            else:
                msg = 'Geometry type %s not implemented' % self.geometry_type
                raise Exception(msg)

            feature.SetGeometry(geom)

            G = feature.GetGeometryRef()
            if G is None:
                msg = 'Could not create GeometryRef for file %s' % filename
                raise Exception(msg)

            # Store attributes
            if store_attributes:
                for j, name in enumerate(fields):
                    actual_field_name = layer_def.GetFieldDefn(j).GetNameRef()

                    val = data[i][name]

                    if type(val) == numpy.ndarray:
                        # A singleton of type <type 'numpy.ndarray'> works
                        # for gdal version 1.6 but fails for version 1.8
                        # in SetField with error: NotImplementedError:
                        # Wrong number of arguments for overloaded function
                        val = float(val)
                    elif val is None:
                        val = ''

                    feature.SetField(actual_field_name, val)

            # Save this feature
            if lyr.CreateFeature(feature) != 0:
                msg = 'Failed to create feature %i in file %s' % (i, filename)
                raise Exception(msg)

            feature.Destroy()

        # Write keywords if any
        write_keywords(self.keywords, basename + '.keywords')