コード例 #1
0
ファイル: test_storage.py プロジェクト: inasafe/safe-geonode
    def test_native_raster_resolution(self):
        """Raster layer retains native resolution through Geoserver

        Raster layer can be uploaded and downloaded again with
        native resolution. This is one test for ticket #103
        """

        hazard_filename = os.path.join(UNITDATA, 'hazard',
                                       'jakarta_flood_design.tif')

        # Get reference values
        H = read_layer(hazard_filename)
        A_ref = H.get_data(nan=True)
        depth_min_ref, depth_max_ref = H.get_extrema()

        # Upload to internal geonode
        hazard_layer = save_to_geonode(hazard_filename, user=self.user)
        hazard_name = '%s:%s' % (hazard_layer.workspace, hazard_layer.name)

        # Download data again with native resolution
        bbox = get_bounding_box_string(hazard_filename)
        H = download(INTERNAL_SERVER_URL, hazard_name, bbox)
        A = H.get_data(nan=True)

        # Compare shapes
        msg = ('Shape of downloaded raster was [%i, %i]. '
               'Expected [%i, %i].' %
               (A.shape[0], A.shape[1], A_ref.shape[0], A_ref.shape[1]))
        assert numpy.allclose(A_ref.shape, A.shape, rtol=0, atol=0), msg

        # Compare extrema to values reference values (which have also been
        # verified by QGIS for this layer and tested in test_engine.py)
        depth_min, depth_max = H.get_extrema()
        msg = ('Extrema of downloaded file were [%f, %f] but '
               'expected [%f, %f]' %
               (depth_min, depth_max, depth_min_ref, depth_max_ref))
        assert numpy.allclose([depth_min, depth_max],
                              [depth_min_ref, depth_max_ref],
                              rtol=1.0e-6,
                              atol=1.0e-10), msg

        # Compare data number by number
        assert nanallclose(A, A_ref, rtol=1.0e-8)
コード例 #2
0
ファイル: test_storage.py プロジェクト: inasafe/safe-geonode
    def test_native_raster_resolution(self):
        """Raster layer retains native resolution through Geoserver

        Raster layer can be uploaded and downloaded again with
        native resolution. This is one test for ticket #103
        """

        hazard_filename = os.path.join(UNITDATA, 'hazard', 'jakarta_flood_design.tif')

        # Get reference values
        H = read_layer(hazard_filename)
        A_ref = H.get_data(nan=True)
        depth_min_ref, depth_max_ref = H.get_extrema()

        # Upload to internal geonode
        hazard_layer = save_to_geonode(hazard_filename, user=self.user)
        hazard_name = '%s:%s' % (hazard_layer.workspace, hazard_layer.name)

        # Download data again with native resolution
        bbox = get_bounding_box_string(hazard_filename)
        H = download(INTERNAL_SERVER_URL, hazard_name, bbox)
        A = H.get_data(nan=True)

        # Compare shapes
        msg = ('Shape of downloaded raster was [%i, %i]. '
               'Expected [%i, %i].' % (A.shape[0], A.shape[1],
                                       A_ref.shape[0], A_ref.shape[1]))
        assert numpy.allclose(A_ref.shape, A.shape, rtol=0, atol=0), msg

        # Compare extrema to values reference values (which have also been
        # verified by QGIS for this layer and tested in test_engine.py)
        depth_min, depth_max = H.get_extrema()
        msg = ('Extrema of downloaded file were [%f, %f] but '
               'expected [%f, %f]' % (depth_min, depth_max,
                                      depth_min_ref, depth_max_ref))
        assert numpy.allclose([depth_min, depth_max],
                              [depth_min_ref, depth_max_ref],
                              rtol=1.0e-6, atol=1.0e-10), msg

        # Compare data number by number
        assert nanallclose(A, A_ref, rtol=1.0e-8)
コード例 #3
0
ファイル: test_storage.py プロジェクト: inasafe/safe-geonode
    def test_data_resampling_example(self):
        """Raster data is unchanged when going through geonode

        """

        # Name file names for hazard level, exposure and expected fatalities
        hazard_filename = os.path.join(TESTDATA, '..', 'hazard', 'maumere_aos_depth_20m_land_wgs84.asc')
        exposure_filename = os.path.join(TESTDATA, 'maumere_pop_prj.shp')

        #------------
        # Hazard data
        #------------
        # Read hazard input data for reference
        H_ref = read_layer(hazard_filename)

        A_ref = H_ref.get_data()
        depth_min_ref, depth_max_ref = H_ref.get_extrema()

        # Upload to internal geonode
        hazard_layer = save_to_geonode(hazard_filename, user=self.user)
        hazard_name = '%s:%s' % (hazard_layer.workspace, hazard_layer.name)

        # Download data again
        bbox = get_bounding_box_string(hazard_filename)  # The biggest
        H = download(INTERNAL_SERVER_URL, hazard_name, bbox)

        A = H.get_data()
        depth_min, depth_max = H.get_extrema()

        # FIXME (Ole): The layer read from file is single precision only:
        # Issue #17
        # Here's the explanation why interpolation below produce slightly
        # different results (but why?)
        # The layer read from file is single precision which may be due to
        # the way it is converted from ASC to TIF. In other words the
        # problem may be in raster.write_to_file. Float64 is
        # specified there, so this is a mystery.
        #print 'A', A.dtype          # Double precision
        #print 'A_ref', A_ref.dtype  # Single precision

        # Compare extrema to values from numpy array
        assert numpy.allclose(depth_max, numpy.nanmax(A),
                              rtol=1.0e-12, atol=1.0e-12)

        assert numpy.allclose(depth_max_ref, numpy.nanmax(A_ref),
                              rtol=1.0e-12, atol=1.0e-12)

        # Compare to reference
        assert numpy.allclose([depth_min, depth_max],
                              [depth_min_ref, depth_max_ref],
                              rtol=1.0e-12, atol=1.0e-12)

        # Compare extrema to values read off QGIS for this layer
        assert numpy.allclose([depth_min, depth_max], [0.0, 16.68],
                              rtol=1.0e-6, atol=1.0e-10)

        # Investigate difference visually
        #from matplotlib.pyplot import matshow, show
        #matshow(A)
        #matshow(A_ref)
        #matshow(A - A_ref)
        #show()

        #print
        for i in range(A.shape[0]):
            for j in range(A.shape[1]):
                if not numpy.isnan(A[i, j]):
                    err = abs(A[i, j] - A_ref[i, j])
                    if err > 0:
                        msg = ('%i, %i: %.15f, %.15f, %.15f'
                               % (i, j, A[i, j], A_ref[i, j], err))
                        raise Exception(msg)
                    #if A[i,j] > 16:
                    #    print i, j, A[i, j], A_ref[i, j]

        # Compare elements (nan & numbers)
        id_nan = numpy.isnan(A)
        id_nan_ref = numpy.isnan(A_ref)
        assert numpy.all(id_nan == id_nan_ref)
        assert numpy.allclose(A[-id_nan], A_ref[-id_nan],
                              rtol=1.0e-15, atol=1.0e-15)

        #print 'MAX', A[245, 283], A_ref[245, 283]
        #print 'MAX: %.15f %.15f %.15f' %(A[245, 283], A_ref[245, 283])
        assert numpy.allclose(A[245, 283], A_ref[245, 283],
                              rtol=1.0e-15, atol=1.0e-15)

        #--------------
        # Exposure data
        #--------------
        # Read exposure input data for reference
        E_ref = read_layer(exposure_filename)

        # Upload to internal geonode
        exposure_layer = save_to_geonode(exposure_filename, user=self.user)
        exposure_name = '%s:%s' % (exposure_layer.workspace,
                                   exposure_layer.name)

        # Download data again
        E = download(INTERNAL_SERVER_URL, exposure_name, bbox)

        # Check exposure data against reference
        coordinates = E.get_geometry()
        coordinates_ref = E_ref.get_geometry()
        assert numpy.allclose(coordinates, coordinates_ref,
                              rtol=1.0e-12, atol=1.0e-12)

        attributes = E.get_data()
        attributes_ref = E_ref.get_data()
        for i, att in enumerate(attributes):
            att_ref = attributes_ref[i]
            for key in att:
                assert att[key] == att_ref[key]

        # Test safe's interpolation function
        I = assign_hazard_values_to_exposure_data(H, E, attribute_name='depth')
        icoordinates = I.get_geometry()

        I_ref = assign_hazard_values_to_exposure_data(H_ref, E_ref, attribute_name='depth')
        icoordinates_ref = I_ref.get_geometry()

        assert numpy.allclose(coordinates,
                              icoordinates,
                              rtol=1.0e-12, atol=1.0e-12)
        assert numpy.allclose(coordinates,
                              icoordinates_ref,
                              rtol=1.0e-12, atol=1.0e-12)

        iattributes = I.get_data()
        assert numpy.allclose(icoordinates, coordinates)

        N = len(icoordinates)
        assert N == 891

        # Set tolerance for single precision until issue #17 has been fixed
        # It appears that the single precision leads to larger interpolation
        # errors
        rtol_issue17 = 2.0e-3
        atol_issue17 = 1.0e-4

        # Verify interpolated values with test result
        for i in range(N):

            interpolated_depth_ref = I_ref.get_data()[i]['depth']
            interpolated_depth = iattributes[i]['depth']

            assert nanallclose(interpolated_depth,
                               interpolated_depth_ref,
                               rtol=rtol_issue17, atol=atol_issue17)

            pointid = attributes[i]['POINTID']

            if pointid == 263:

                #print i, pointid, attributes[i],
                #print interpolated_depth, coordinates[i]

                # Check that location is correct
                assert numpy.allclose(coordinates[i],
                                      [122.20367299, -8.61300358],
                                      rtol=1.0e-7, atol=1.0e-12)

                # This is known to be outside inundation area so should
                # near zero
                assert numpy.allclose(interpolated_depth, 0.0,
                                      rtol=1.0e-12, atol=1.0e-12)

            if pointid == 148:
                # Check that location is correct
                #print coordinates[i]
                assert numpy.allclose(coordinates[i],
                                      [122.2045912, -8.608483265],
                                      rtol=1.0e-7, atol=1.0e-12)

                # This is in an inundated area with a surrounding depths of
                # 4.531, 3.911
                # 2.675, 2.583
                assert interpolated_depth < 4.531
                assert interpolated_depth < 3.911
                assert interpolated_depth > 2.583
                assert interpolated_depth > 2.675

                #print interpolated_depth
                # This is a characterisation test for bilinear interpolation
                assert numpy.allclose(interpolated_depth, 3.62477215491,
                                      rtol=rtol_issue17, atol=1.0e-12)

            # Check that interpolated points are within range
            msg = ('Interpolated depth %f at point %i was outside extrema: '
                   '[%f, %f]. ' % (interpolated_depth, i,
                                   depth_min, depth_max))

            if not numpy.isnan(interpolated_depth):
                assert depth_min <= interpolated_depth <= depth_max, msg
コード例 #4
0
ファイル: test_storage.py プロジェクト: inasafe/safe-geonode
    def test_raster_scaling(self):
        """Raster layers can be scaled when resampled

        This is a test for ticket #168

        Native test .asc data has

        ncols         5525
        nrows         2050
        cellsize      0.0083333333333333

        Scaling is necessary for raster data that represents density
        such as population per km^2
        """

        for test_filename in ['jakarta_flood_design.tif']:

            raster_filename = os.path.join(UNITDATA, 'hazard', test_filename)

            # Get reference values
            R = read_layer(raster_filename)
            R_min_ref, R_max_ref = R.get_extrema()
            native_resolution = R.get_resolution()

            # Upload to internal geonode
            raster_layer = save_to_geonode(raster_filename, user=self.user)
            raster_name = '%s:%s' % (raster_layer.workspace,
                                     raster_layer.name)

            # Test for a range of resolutions
            for res in [0.01, 0.005, 0.002, 0.001, 0.0005, 0.0002]:

                bbox = get_bounding_box_string(raster_filename)

                R = download(INTERNAL_SERVER_URL, raster_name,
                             bbox, resolution=res)
                A_native = R.get_data(scaling=False)
                A_scaled = R.get_data(scaling=True)

                sigma = (R.get_resolution()[0] / native_resolution[0]) ** 2

                # Compare extrema
                expected_scaled_max = sigma * numpy.nanmax(A_native)
                msg = ('Resampled raster was not rescaled correctly: '
                       'max(A_scaled) was %f but expected %f'
                       % (numpy.nanmax(A_scaled), expected_scaled_max))

                assert numpy.allclose(expected_scaled_max,
                                      numpy.nanmax(A_scaled),
                                      rtol=1.0e0, atol=1.0e-1), msg

                expected_scaled_min = sigma * numpy.nanmin(A_native)
                msg = ('Resampled raster was not rescaled correctly: '
                       'min(A_scaled) was %f but expected %f'
                       % (numpy.nanmin(A_scaled), expected_scaled_min))
                assert numpy.allclose(expected_scaled_min,
                                      numpy.nanmin(A_scaled),
                                      rtol=1.0e0, atol=1.0e-1), msg

                # Compare elementwise
                msg = 'Resampled raster was not rescaled correctly'
                assert nanallclose(A_native * sigma, A_scaled,
                                   rtol=1.0e0, atol=1.0e-1), msg

                # Check that it also works with manual scaling
                A_manual = R.get_data(scaling=sigma)
                msg = 'Resampled raster was not rescaled correctly'
                assert nanallclose(A_manual, A_scaled,
                                   rtol=1.0e0, atol=1.0e-1), msg

                # Check that an exception is raised for bad arguments
                try:
                    R.get_data(scaling='bad')
                except:
                    pass
                else:
                    msg = 'String argument should have raised exception'
                    raise Exception(msg)

                try:
                    R.get_data(scaling='(1, 3)')
                except:
                    pass
                else:
                    msg = 'Tuple argument should have raised exception'
                    raise Exception(msg)

                # Check None option without existence of density keyword
                A_none = R.get_data(scaling=None)
                msg = 'Data should not have changed'
                assert nanallclose(A_native, A_none,
                                   rtol=1.0e-0, atol=1.0e-1), msg

                # Try with None and density keyword
                R.keywords['density'] = 'true'
                A_none = R.get_data(scaling=None)
                msg = 'Resampled raster was not rescaled correctly'
                assert nanallclose(A_scaled, A_none,
                                   rtol=1.0e2, atol=1.0e2), msg

                R.keywords['density'] = 'Yes'
                A_none = R.get_data(scaling=None)
                msg = 'Resampled raster was not rescaled correctly'
                assert nanallclose(A_scaled, A_none,
                                   rtol=1.0e2, atol=1.0e2), msg

                R.keywords['density'] = 'False'
                A_none = R.get_data(scaling=None)
                msg = 'Data should not have changed'
                assert nanallclose(A_native, A_none,
                                   rtol=1.0e2, atol=1.0e2), msg

                R.keywords['density'] = 'no'
                A_none = R.get_data(scaling=None)
                msg = 'Data should not have changed'
                assert nanallclose(A_native, A_none,
                                   rtol=1.0e2, atol=1.0e2), msg
コード例 #5
0
ファイル: test_storage.py プロジェクト: inasafe/safe-geonode
    def test_data_resampling_example(self):
        """Raster data is unchanged when going through geonode

        """

        # Name file names for hazard level, exposure and expected fatalities
        hazard_filename = os.path.join(TESTDATA, '..', 'hazard',
                                       'maumere_aos_depth_20m_land_wgs84.asc')
        exposure_filename = os.path.join(TESTDATA, 'maumere_pop_prj.shp')

        #------------
        # Hazard data
        #------------
        # Read hazard input data for reference
        H_ref = read_layer(hazard_filename)

        A_ref = H_ref.get_data()
        depth_min_ref, depth_max_ref = H_ref.get_extrema()

        # Upload to internal geonode
        hazard_layer = save_to_geonode(hazard_filename, user=self.user)
        hazard_name = '%s:%s' % (hazard_layer.workspace, hazard_layer.name)

        # Download data again
        bbox = get_bounding_box_string(hazard_filename)  # The biggest
        H = download(INTERNAL_SERVER_URL, hazard_name, bbox)

        A = H.get_data()
        depth_min, depth_max = H.get_extrema()

        # FIXME (Ole): The layer read from file is single precision only:
        # Issue #17
        # Here's the explanation why interpolation below produce slightly
        # different results (but why?)
        # The layer read from file is single precision which may be due to
        # the way it is converted from ASC to TIF. In other words the
        # problem may be in raster.write_to_file. Float64 is
        # specified there, so this is a mystery.
        #print 'A', A.dtype          # Double precision
        #print 'A_ref', A_ref.dtype  # Single precision

        # Compare extrema to values from numpy array
        assert numpy.allclose(depth_max,
                              numpy.nanmax(A),
                              rtol=1.0e-12,
                              atol=1.0e-12)

        assert numpy.allclose(depth_max_ref,
                              numpy.nanmax(A_ref),
                              rtol=1.0e-12,
                              atol=1.0e-12)

        # Compare to reference
        assert numpy.allclose([depth_min, depth_max],
                              [depth_min_ref, depth_max_ref],
                              rtol=1.0e-12,
                              atol=1.0e-12)

        # Compare extrema to values read off QGIS for this layer
        assert numpy.allclose([depth_min, depth_max], [0.0, 16.68],
                              rtol=1.0e-6,
                              atol=1.0e-10)

        # Investigate difference visually
        #from matplotlib.pyplot import matshow, show
        #matshow(A)
        #matshow(A_ref)
        #matshow(A - A_ref)
        #show()

        #print
        for i in range(A.shape[0]):
            for j in range(A.shape[1]):
                if not numpy.isnan(A[i, j]):
                    err = abs(A[i, j] - A_ref[i, j])
                    if err > 0:
                        msg = ('%i, %i: %.15f, %.15f, %.15f' %
                               (i, j, A[i, j], A_ref[i, j], err))
                        raise Exception(msg)
                    #if A[i,j] > 16:
                    #    print i, j, A[i, j], A_ref[i, j]

        # Compare elements (nan & numbers)
        id_nan = numpy.isnan(A)
        id_nan_ref = numpy.isnan(A_ref)
        assert numpy.all(id_nan == id_nan_ref)
        assert numpy.allclose(A[-id_nan],
                              A_ref[-id_nan],
                              rtol=1.0e-15,
                              atol=1.0e-15)

        #print 'MAX', A[245, 283], A_ref[245, 283]
        #print 'MAX: %.15f %.15f %.15f' %(A[245, 283], A_ref[245, 283])
        assert numpy.allclose(A[245, 283],
                              A_ref[245, 283],
                              rtol=1.0e-15,
                              atol=1.0e-15)

        #--------------
        # Exposure data
        #--------------
        # Read exposure input data for reference
        E_ref = read_layer(exposure_filename)

        # Upload to internal geonode
        exposure_layer = save_to_geonode(exposure_filename, user=self.user)
        exposure_name = '%s:%s' % (exposure_layer.workspace,
                                   exposure_layer.name)

        # Download data again
        E = download(INTERNAL_SERVER_URL, exposure_name, bbox)

        # Check exposure data against reference
        coordinates = E.get_geometry()
        coordinates_ref = E_ref.get_geometry()
        assert numpy.allclose(coordinates,
                              coordinates_ref,
                              rtol=1.0e-12,
                              atol=1.0e-12)

        attributes = E.get_data()
        attributes_ref = E_ref.get_data()
        for i, att in enumerate(attributes):
            att_ref = attributes_ref[i]
            for key in att:
                assert att[key] == att_ref[key]

        # Test safe's interpolation function
        I = assign_hazard_values_to_exposure_data(H, E, attribute_name='depth')
        icoordinates = I.get_geometry()

        I_ref = assign_hazard_values_to_exposure_data(H_ref,
                                                      E_ref,
                                                      attribute_name='depth')
        icoordinates_ref = I_ref.get_geometry()

        assert numpy.allclose(coordinates,
                              icoordinates,
                              rtol=1.0e-12,
                              atol=1.0e-12)
        assert numpy.allclose(coordinates,
                              icoordinates_ref,
                              rtol=1.0e-12,
                              atol=1.0e-12)

        iattributes = I.get_data()
        assert numpy.allclose(icoordinates, coordinates)

        N = len(icoordinates)
        assert N == 891

        # Set tolerance for single precision until issue #17 has been fixed
        # It appears that the single precision leads to larger interpolation
        # errors
        rtol_issue17 = 2.0e-3
        atol_issue17 = 1.0e-4

        # Verify interpolated values with test result
        for i in range(N):

            interpolated_depth_ref = I_ref.get_data()[i]['depth']
            interpolated_depth = iattributes[i]['depth']

            assert nanallclose(interpolated_depth,
                               interpolated_depth_ref,
                               rtol=rtol_issue17,
                               atol=atol_issue17)

            pointid = attributes[i]['POINTID']

            if pointid == 263:

                #print i, pointid, attributes[i],
                #print interpolated_depth, coordinates[i]

                # Check that location is correct
                assert numpy.allclose(coordinates[i],
                                      [122.20367299, -8.61300358],
                                      rtol=1.0e-7,
                                      atol=1.0e-12)

                # This is known to be outside inundation area so should
                # near zero
                assert numpy.allclose(interpolated_depth,
                                      0.0,
                                      rtol=1.0e-12,
                                      atol=1.0e-12)

            if pointid == 148:
                # Check that location is correct
                #print coordinates[i]
                assert numpy.allclose(coordinates[i],
                                      [122.2045912, -8.608483265],
                                      rtol=1.0e-7,
                                      atol=1.0e-12)

                # This is in an inundated area with a surrounding depths of
                # 4.531, 3.911
                # 2.675, 2.583
                assert interpolated_depth < 4.531
                assert interpolated_depth < 3.911
                assert interpolated_depth > 2.583
                assert interpolated_depth > 2.675

                #print interpolated_depth
                # This is a characterisation test for bilinear interpolation
                assert numpy.allclose(interpolated_depth,
                                      3.62477215491,
                                      rtol=rtol_issue17,
                                      atol=1.0e-12)

            # Check that interpolated points are within range
            msg = ('Interpolated depth %f at point %i was outside extrema: '
                   '[%f, %f]. ' %
                   (interpolated_depth, i, depth_min, depth_max))

            if not numpy.isnan(interpolated_depth):
                assert depth_min <= interpolated_depth <= depth_max, msg
コード例 #6
0
ファイル: test_storage.py プロジェクト: inasafe/safe-geonode
    def test_raster_scaling(self):
        """Raster layers can be scaled when resampled

        This is a test for ticket #168

        Native test .asc data has

        ncols         5525
        nrows         2050
        cellsize      0.0083333333333333

        Scaling is necessary for raster data that represents density
        such as population per km^2
        """

        for test_filename in ['jakarta_flood_design.tif']:

            raster_filename = os.path.join(UNITDATA, 'hazard', test_filename)

            # Get reference values
            R = read_layer(raster_filename)
            R_min_ref, R_max_ref = R.get_extrema()
            native_resolution = R.get_resolution()

            # Upload to internal geonode
            raster_layer = save_to_geonode(raster_filename, user=self.user)
            raster_name = '%s:%s' % (raster_layer.workspace, raster_layer.name)

            # Test for a range of resolutions
            for res in [0.01, 0.005, 0.002, 0.001, 0.0005, 0.0002]:

                bbox = get_bounding_box_string(raster_filename)

                R = download(INTERNAL_SERVER_URL,
                             raster_name,
                             bbox,
                             resolution=res)
                A_native = R.get_data(scaling=False)
                A_scaled = R.get_data(scaling=True)

                sigma = (R.get_resolution()[0] / native_resolution[0])**2

                # Compare extrema
                expected_scaled_max = sigma * numpy.nanmax(A_native)
                msg = ('Resampled raster was not rescaled correctly: '
                       'max(A_scaled) was %f but expected %f' %
                       (numpy.nanmax(A_scaled), expected_scaled_max))

                assert numpy.allclose(expected_scaled_max,
                                      numpy.nanmax(A_scaled),
                                      rtol=1.0e0,
                                      atol=1.0e-1), msg

                expected_scaled_min = sigma * numpy.nanmin(A_native)
                msg = ('Resampled raster was not rescaled correctly: '
                       'min(A_scaled) was %f but expected %f' %
                       (numpy.nanmin(A_scaled), expected_scaled_min))
                assert numpy.allclose(expected_scaled_min,
                                      numpy.nanmin(A_scaled),
                                      rtol=1.0e0,
                                      atol=1.0e-1), msg

                # Compare elementwise
                msg = 'Resampled raster was not rescaled correctly'
                assert nanallclose(A_native * sigma,
                                   A_scaled,
                                   rtol=1.0e0,
                                   atol=1.0e-1), msg

                # Check that it also works with manual scaling
                A_manual = R.get_data(scaling=sigma)
                msg = 'Resampled raster was not rescaled correctly'
                assert nanallclose(A_manual, A_scaled, rtol=1.0e0,
                                   atol=1.0e-1), msg

                # Check that an exception is raised for bad arguments
                try:
                    R.get_data(scaling='bad')
                except:
                    pass
                else:
                    msg = 'String argument should have raised exception'
                    raise Exception(msg)

                try:
                    R.get_data(scaling='(1, 3)')
                except:
                    pass
                else:
                    msg = 'Tuple argument should have raised exception'
                    raise Exception(msg)

                # Check None option without existence of density keyword
                A_none = R.get_data(scaling=None)
                msg = 'Data should not have changed'
                assert nanallclose(A_native, A_none, rtol=1.0e-0,
                                   atol=1.0e-1), msg

                # Try with None and density keyword
                R.keywords['density'] = 'true'
                A_none = R.get_data(scaling=None)
                msg = 'Resampled raster was not rescaled correctly'
                assert nanallclose(A_scaled, A_none, rtol=1.0e2,
                                   atol=1.0e2), msg

                R.keywords['density'] = 'Yes'
                A_none = R.get_data(scaling=None)
                msg = 'Resampled raster was not rescaled correctly'
                assert nanallclose(A_scaled, A_none, rtol=1.0e2,
                                   atol=1.0e2), msg

                R.keywords['density'] = 'False'
                A_none = R.get_data(scaling=None)
                msg = 'Data should not have changed'
                assert nanallclose(A_native, A_none, rtol=1.0e2,
                                   atol=1.0e2), msg

                R.keywords['density'] = 'no'
                A_none = R.get_data(scaling=None)
                msg = 'Data should not have changed'
                assert nanallclose(A_native, A_none, rtol=1.0e2,
                                   atol=1.0e2), msg