Example #1
0
    def resample(self, target_area_def):
        """Resamples image to area definition using nearest neighbour
        approach in projection coordinates.

        Parameters
        ----------
        target_area_def : object
            Target area definition as AreaDefinition object

        Returns
        -------
        image_container : object
            ImageContainerQuick object of resampled area
        """

        resampled_image = grid.get_resampled_image(target_area_def,
                                                   self.geo_def,
                                                   self.image_data,
                                                   fill_value=self.fill_value,
                                                   nprocs=self.nprocs,
                                                   segments=self.segments)

        return ImageContainerQuick(resampled_image, target_area_def,
                                   fill_value=self.fill_value,
                                   nprocs=self.nprocs, segments=self.segments)
Example #2
0
    def resample(self, target_area_def):
        """Resamples image to area definition using nearest neighbour
        approach in projection coordinates.

        Parameters
        ----------
        target_area_def : object
            Target area definition as AreaDefinition object

        Returns
        -------
        image_container : object
            ImageContainerQuick object of resampled area
        """

        resampled_image = grid.get_resampled_image(target_area_def,
                                                   self.geo_def,
                                                   self.image_data,
                                                   fill_value=self.fill_value,
                                                   nprocs=self.nprocs,
                                                   segments=self.segments)

        return ImageContainerQuick(resampled_image,
                                   target_area_def,
                                   fill_value=self.fill_value,
                                   nprocs=self.nprocs,
                                   segments=self.segments)
Example #3
0
def convert_files():
    """
    Converts all files in a directory of .nc files into 500x500 .npy files of California brightness temperatures, 
    and deletes the originals. If the conversion fails, the file name is written to a log.
    """
    convert_log = open("../../GOES_Files/convert_log.txt", "w")
    fail_log = open("../../GOES_Files/fail_log.txt", "w")
    for file in os.listdir('../../GOES_Files/nc_files/'):
        try:
            data = xr.open_dataset('../../GOES_Files/nc_files/' + file)
            dat = data.metpy.parse_cf('Rad')
            geos = dat.metpy.cartopy_crs
            rad = dat.data

            fk1 = float(data.metpy.parse_cf('planck_fk1'))
            fk2 = float(data.metpy.parse_cf('planck_fk2'))
            bc1 = float(data.metpy.parse_cf('planck_bc1'))
            bc2 = float(data.metpy.parse_cf('planck_bc2'))
            bt = (fk2 / (xr.ufuncs.log(fk1 / rad + 1)) - bc1) / bc2
            bt = np.asarray(bt)

            goes_params = geos.proj4_params
            source_area = geometry.AreaDefinition.from_cf(data)
            target_area = geometry.AreaDefinition.from_extent(
                'CA', pc_params, shape, target_extents)

            result = grid.get_resampled_image(target_area, source_area, bt)
            np.save('../../GOES_Files/npy_files/' + file[:-3], result)
            data.close()
            os.remove('../../GOES_Files/nc_files/' + file)
            convert_log.write('\n' + file)
        except:
            fail_log.write('\n' + file)
    convert_log.close()
    fail_log.close()
Example #4
0
 def test_resampled_image_mp(self):
     data = np.fromfunction(lambda y, x: y*x*10**-6, (3712, 3712))
     target_def = self.area_def
     source_def = self.msg_area
     res = grid.get_resampled_image(target_def, source_def, data, nprocs=2, segments=1)
     cross_sum = res.sum()
     expected = 399936.39392500359
     self.assertAlmostEqual(cross_sum, expected, msg='Resampling of image mp failed')
Example #5
0
 def test_resampled_image_mp(self):
     data = np.fromfunction(lambda y, x: y * x * 10 ** -6, (3712, 3712))
     target_def = self.area_def
     source_def = self.msg_area
     res = grid.get_resampled_image(
         target_def, source_def, data, nprocs=2, segments=1)
     cross_sum = res.sum()
     expected = 399936.39392500359
     self.assertAlmostEqual(
         cross_sum, expected, msg='Resampling of image mp failed')
Example #6
0
    def test_resampled_image_masked(self):
        # Generate test image with masked elements
        data = np.ma.ones(self.msg_area.shape)
        data.mask = np.zeros(data.shape)
        data.mask[253:400, 1970:2211] = 1

        # Resample image using multiple segments
        target_def = self.area_def
        source_def = self.msg_area
        res = grid.get_resampled_image(
            target_def, source_def, data, segments=4, fill_value=None)

        # Make sure the mask has been preserved
        self.assertGreater(res.mask.sum(), 0,
                           msg='Resampling did not preserve the mask')
Example #7
0
    def test_resampled_image_masked(self):
        # Generate test image with masked elements
        data = np.ma.ones(self.msg_area.shape)
        data.mask = np.zeros(data.shape)
        data.mask[253:400, 1970:2211] = 1

        # Resample image using multiple segments
        target_def = self.area_def
        source_def = self.msg_area
        res = grid.get_resampled_image(
            target_def, source_def, data, segments=4, fill_value=None)

        # Make sure the mask has been preserved
        self.assertGreater(res.mask.sum(), 0,
                           msg='Resampling did not preserve the mask')