#!/usr/bin/env python
# -*- coding: utf-8 -*-
# Copyright (c) 2017-2019 Satpy developers
#
# This file is part of satpy.
#
# satpy is free software: you can redistribute it and/or modify it under the
# terms of the GNU General Public License as published by the Free Software
# Foundation, either version 3 of the License, or (at your option) any later
# version.
#
# satpy is distributed in the hope that it will be useful, but WITHOUT ANY
# WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
# A PARTICULAR PURPOSE. See the GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License along with
# satpy. If not, see <http://www.gnu.org/licenses/>.
"""Tests for the CF writer."""
import logging
import os
import tempfile
import unittest
import warnings
from collections import OrderedDict
from datetime import datetime
from unittest import mock
import numpy as np
import pytest
import xarray as xr
from packaging.version import Version
from satpy import Scene
from satpy.tests.utils import make_dsq
from satpy.writers.cf_writer import _get_backend_versions
try:
from pyproj import CRS
except ImportError:
CRS = None
# NOTE:
# The following fixtures are not defined in this file, but are used and injected by Pytest:
# - tmp_path
# - caplog
# - request
[docs]class TempFile(object):
"""A temporary filename class."""
def __init__(self, suffix=".nc"):
"""Initialize."""
self.filename = None
self.suffix = suffix
def __enter__(self):
"""Enter."""
self.handle, self.filename = tempfile.mkstemp(suffix=self.suffix)
os.close(self.handle)
return self.filename
def __exit__(self, *args):
"""Exit."""
os.remove(self.filename)
[docs]class TestCFWriter(unittest.TestCase):
"""Test case for CF writer."""
[docs] def test_init(self):
"""Test initializing the CFWriter class."""
from satpy.writers import configs_for_writer
from satpy.writers.cf_writer import CFWriter
CFWriter(config_files=list(configs_for_writer('cf'))[0])
[docs] def test_save_array(self):
"""Test saving an array to netcdf/cf."""
import xarray as xr
from satpy import Scene
scn = Scene()
start_time = datetime(2018, 5, 30, 10, 0)
end_time = datetime(2018, 5, 30, 10, 15)
scn['test-array'] = xr.DataArray([1, 2, 3],
attrs=dict(start_time=start_time,
end_time=end_time,
prerequisites=[make_dsq(name='hej')]))
with TempFile() as filename:
scn.save_datasets(filename=filename, writer='cf')
with xr.open_dataset(filename) as f:
np.testing.assert_array_equal(f['test-array'][:], [1, 2, 3])
expected_prereq = ("DataQuery(name='hej')")
self.assertEqual(f['test-array'].attrs['prerequisites'],
expected_prereq)
[docs] def test_save_array_coords(self):
"""Test saving array with coordinates."""
import numpy as np
import xarray as xr
from satpy import Scene
scn = Scene()
start_time = datetime(2018, 5, 30, 10, 0)
end_time = datetime(2018, 5, 30, 10, 15)
coords = {
'x': np.arange(3),
'y': np.arange(1),
}
if CRS is not None:
proj_str = ('+proj=geos +lon_0=-95.0 +h=35786023.0 '
'+a=6378137.0 +b=6356752.31414 +sweep=x '
'+units=m +no_defs')
coords['crs'] = CRS.from_string(proj_str)
scn['test-array'] = xr.DataArray([[1, 2, 3]],
dims=('y', 'x'),
coords=coords,
attrs=dict(start_time=start_time,
end_time=end_time,
prerequisites=[make_dsq(name='hej')]))
with TempFile() as filename:
scn.save_datasets(filename=filename, writer='cf')
with xr.open_dataset(filename) as f:
np.testing.assert_array_equal(f['test-array'][:], [[1, 2, 3]])
np.testing.assert_array_equal(f['x'][:], [0, 1, 2])
np.testing.assert_array_equal(f['y'][:], [0])
self.assertNotIn('crs', f)
self.assertNotIn('_FillValue', f['x'].attrs)
self.assertNotIn('_FillValue', f['y'].attrs)
expected_prereq = ("DataQuery(name='hej')")
self.assertEqual(f['test-array'].attrs['prerequisites'],
expected_prereq)
[docs] def test_save_dataset_a_digit(self):
"""Test saving an array to netcdf/cf where dataset name starting with a digit."""
import xarray as xr
from satpy import Scene
scn = Scene()
scn['1'] = xr.DataArray([1, 2, 3])
with TempFile() as filename:
scn.save_datasets(filename=filename, writer='cf')
with xr.open_dataset(filename) as f:
np.testing.assert_array_equal(f['CHANNEL_1'][:], [1, 2, 3])
[docs] def test_save_dataset_a_digit_prefix(self):
"""Test saving an array to netcdf/cf where dataset name starting with a digit with prefix."""
import xarray as xr
from satpy import Scene
scn = Scene()
scn['1'] = xr.DataArray([1, 2, 3])
with TempFile() as filename:
scn.save_datasets(filename=filename, writer='cf', numeric_name_prefix='TEST')
with xr.open_dataset(filename) as f:
np.testing.assert_array_equal(f['TEST1'][:], [1, 2, 3])
[docs] def test_save_dataset_a_digit_prefix_include_attr(self):
"""Test saving an array to netcdf/cf where dataset name starting with a digit with prefix include orig name."""
import xarray as xr
from satpy import Scene
scn = Scene()
scn['1'] = xr.DataArray([1, 2, 3])
with TempFile() as filename:
scn.save_datasets(filename=filename, writer='cf', include_orig_name=True, numeric_name_prefix='TEST')
with xr.open_dataset(filename) as f:
np.testing.assert_array_equal(f['TEST1'][:], [1, 2, 3])
self.assertEqual(f['TEST1'].attrs['original_name'], '1')
[docs] def test_save_dataset_a_digit_no_prefix_include_attr(self):
"""Test saving an array to netcdf/cf dataset name starting with a digit with no prefix include orig name."""
import xarray as xr
from satpy import Scene
scn = Scene()
scn['1'] = xr.DataArray([1, 2, 3])
with TempFile() as filename:
scn.save_datasets(filename=filename, writer='cf', include_orig_name=True, numeric_name_prefix='')
with xr.open_dataset(filename) as f:
np.testing.assert_array_equal(f['1'][:], [1, 2, 3])
self.assertNotIn('original_name', f['1'].attrs)
[docs] def test_ancillary_variables(self):
"""Test ancillary_variables cited each other."""
import xarray as xr
from satpy import Scene
from satpy.tests.utils import make_dataid
scn = Scene()
start_time = datetime(2018, 5, 30, 10, 0)
end_time = datetime(2018, 5, 30, 10, 15)
da = xr.DataArray([1, 2, 3],
attrs=dict(start_time=start_time,
end_time=end_time,
prerequisites=[make_dataid(name='hej')]))
scn['test-array-1'] = da
scn['test-array-2'] = da.copy()
scn['test-array-1'].attrs['ancillary_variables'] = [scn['test-array-2']]
scn['test-array-2'].attrs['ancillary_variables'] = [scn['test-array-1']]
with TempFile() as filename:
scn.save_datasets(filename=filename, writer='cf')
with xr.open_dataset(filename) as f:
self.assertEqual(f['test-array-1'].attrs['ancillary_variables'],
'test-array-2')
self.assertEqual(f['test-array-2'].attrs['ancillary_variables'],
'test-array-1')
[docs] def test_groups(self):
"""Test creating a file with groups."""
import xarray as xr
from satpy import Scene
tstart = datetime(2019, 4, 1, 12, 0)
tend = datetime(2019, 4, 1, 12, 15)
data_visir = [[1, 2], [3, 4]]
y_visir = [1, 2]
x_visir = [1, 2]
time_vis006 = [1, 2]
time_ir_108 = [3, 4]
data_hrv = [[1, 2, 3], [4, 5, 6], [7, 8, 9]]
y_hrv = [1, 2, 3]
x_hrv = [1, 2, 3]
time_hrv = [1, 2, 3]
scn = Scene()
scn['VIS006'] = xr.DataArray(data_visir,
dims=('y', 'x'),
coords={'y': y_visir, 'x': x_visir, 'acq_time': ('y', time_vis006)},
attrs={'name': 'VIS006', 'start_time': tstart, 'end_time': tend})
scn['IR_108'] = xr.DataArray(data_visir,
dims=('y', 'x'),
coords={'y': y_visir, 'x': x_visir, 'acq_time': ('y', time_ir_108)},
attrs={'name': 'IR_108', 'start_time': tstart, 'end_time': tend})
scn['HRV'] = xr.DataArray(data_hrv,
dims=('y', 'x'),
coords={'y': y_hrv, 'x': x_hrv, 'acq_time': ('y', time_hrv)},
attrs={'name': 'HRV', 'start_time': tstart, 'end_time': tend})
with TempFile() as filename:
scn.save_datasets(filename=filename, writer='cf', groups={'visir': ['IR_108', 'VIS006'], 'hrv': ['HRV']},
pretty=True)
nc_root = xr.open_dataset(filename)
self.assertIn('history', nc_root.attrs)
self.assertSetEqual(set(nc_root.variables.keys()), set())
nc_visir = xr.open_dataset(filename, group='visir')
nc_hrv = xr.open_dataset(filename, group='hrv')
self.assertSetEqual(set(nc_visir.variables.keys()), {'VIS006', 'IR_108', 'y', 'x', 'VIS006_acq_time',
'IR_108_acq_time'})
self.assertSetEqual(set(nc_hrv.variables.keys()), {'HRV', 'y', 'x', 'acq_time'})
for tst, ref in zip([nc_visir['VIS006'], nc_visir['IR_108'], nc_hrv['HRV']],
[scn['VIS006'], scn['IR_108'], scn['HRV']]):
np.testing.assert_array_equal(tst.data, ref.data)
nc_root.close()
nc_visir.close()
nc_hrv.close()
# Different projection coordinates in one group are not supported
with TempFile() as filename:
self.assertRaises(ValueError, scn.save_datasets, datasets=['VIS006', 'HRV'], filename=filename, writer='cf')
[docs] def test_single_time_value(self):
"""Test setting a single time value."""
import xarray as xr
from satpy import Scene
scn = Scene()
start_time = datetime(2018, 5, 30, 10, 0)
end_time = datetime(2018, 5, 30, 10, 15)
test_array = np.array([[1, 2], [3, 4]])
scn['test-array'] = xr.DataArray(test_array,
dims=['x', 'y'],
coords={'time': np.datetime64('2018-05-30T10:05:00')},
attrs=dict(start_time=start_time,
end_time=end_time))
with TempFile() as filename:
scn.save_datasets(filename=filename, writer='cf')
with xr.open_dataset(filename, decode_cf=True) as f:
np.testing.assert_array_equal(f['time'], scn['test-array']['time'])
bounds_exp = np.array([[start_time, end_time]], dtype='datetime64[m]')
np.testing.assert_array_equal(f['time_bnds'], bounds_exp)
[docs] def test_time_coordinate_on_a_swath(self):
"""Test that time dimension is not added on swath data with time already as a coordinate."""
import xarray as xr
from satpy import Scene
scn = Scene()
test_array = np.array([[1, 2], [3, 4], [5, 6], [7, 8]])
times = np.array(['2018-05-30T10:05:00', '2018-05-30T10:05:01',
'2018-05-30T10:05:02', '2018-05-30T10:05:03'], dtype=np.datetime64)
scn['test-array'] = xr.DataArray(test_array,
dims=['y', 'x'],
coords={'time': ('y', times)},
attrs=dict(start_time=times[0], end_time=times[-1]))
with TempFile() as filename:
scn.save_datasets(filename=filename, writer='cf', pretty=True)
with xr.open_dataset(filename, decode_cf=True) as f:
np.testing.assert_array_equal(f['time'], scn['test-array']['time'])
[docs] def test_bounds(self):
"""Test setting time bounds."""
import xarray as xr
from satpy import Scene
scn = Scene()
start_time = datetime(2018, 5, 30, 10, 0)
end_time = datetime(2018, 5, 30, 10, 15)
test_array = np.array([[1, 2], [3, 4]]).reshape(2, 2, 1)
scn['test-array'] = xr.DataArray(test_array,
dims=['x', 'y', 'time'],
coords={'time': [np.datetime64('2018-05-30T10:05:00')]},
attrs=dict(start_time=start_time,
end_time=end_time))
with TempFile() as filename:
scn.save_datasets(filename=filename, writer='cf')
# Check decoded time coordinates & bounds
with xr.open_dataset(filename, decode_cf=True) as f:
bounds_exp = np.array([[start_time, end_time]], dtype='datetime64[m]')
np.testing.assert_array_equal(f['time_bnds'], bounds_exp)
self.assertEqual(f['time'].attrs['bounds'], 'time_bnds')
# Check raw time coordinates & bounds
with xr.open_dataset(filename, decode_cf=False) as f:
np.testing.assert_almost_equal(f['time_bnds'], [[-0.0034722, 0.0069444]])
# User-specified time encoding should have preference
with TempFile() as filename:
time_units = 'seconds since 2018-01-01'
scn.save_datasets(filename=filename, encoding={'time': {'units': time_units}},
writer='cf')
with xr.open_dataset(filename, decode_cf=False) as f:
np.testing.assert_array_equal(f['time_bnds'], [[12909600, 12910500]])
[docs] def test_bounds_minimum(self):
"""Test minimum bounds."""
import xarray as xr
from satpy import Scene
scn = Scene()
start_timeA = datetime(2018, 5, 30, 10, 0) # expected to be used
end_timeA = datetime(2018, 5, 30, 10, 20)
start_timeB = datetime(2018, 5, 30, 10, 3)
end_timeB = datetime(2018, 5, 30, 10, 15) # expected to be used
test_arrayA = np.array([[1, 2], [3, 4]]).reshape(2, 2, 1)
test_arrayB = np.array([[1, 2], [3, 5]]).reshape(2, 2, 1)
scn['test-arrayA'] = xr.DataArray(test_arrayA,
dims=['x', 'y', 'time'],
coords={'time': [np.datetime64('2018-05-30T10:05:00')]},
attrs=dict(start_time=start_timeA,
end_time=end_timeA))
scn['test-arrayB'] = xr.DataArray(test_arrayB,
dims=['x', 'y', 'time'],
coords={'time': [np.datetime64('2018-05-30T10:05:00')]},
attrs=dict(start_time=start_timeB,
end_time=end_timeB))
with TempFile() as filename:
scn.save_datasets(filename=filename, writer='cf')
with xr.open_dataset(filename, decode_cf=True) as f:
bounds_exp = np.array([[start_timeA, end_timeB]], dtype='datetime64[m]')
np.testing.assert_array_equal(f['time_bnds'], bounds_exp)
[docs] def test_bounds_missing_time_info(self):
"""Test time bounds generation in case of missing time."""
import xarray as xr
from satpy import Scene
scn = Scene()
start_timeA = datetime(2018, 5, 30, 10, 0)
end_timeA = datetime(2018, 5, 30, 10, 15)
test_arrayA = np.array([[1, 2], [3, 4]]).reshape(2, 2, 1)
test_arrayB = np.array([[1, 2], [3, 5]]).reshape(2, 2, 1)
scn['test-arrayA'] = xr.DataArray(test_arrayA,
dims=['x', 'y', 'time'],
coords={'time': [np.datetime64('2018-05-30T10:05:00')]},
attrs=dict(start_time=start_timeA,
end_time=end_timeA))
scn['test-arrayB'] = xr.DataArray(test_arrayB,
dims=['x', 'y', 'time'],
coords={'time': [np.datetime64('2018-05-30T10:05:00')]})
with TempFile() as filename:
scn.save_datasets(filename=filename, writer='cf')
with xr.open_dataset(filename, decode_cf=True) as f:
bounds_exp = np.array([[start_timeA, end_timeA]], dtype='datetime64[m]')
np.testing.assert_array_equal(f['time_bnds'], bounds_exp)
[docs] def test_unlimited_dims_kwarg(self):
"""Test specification of unlimited dimensions."""
import xarray as xr
from satpy import Scene
scn = Scene()
start_time = datetime(2018, 5, 30, 10, 0)
end_time = datetime(2018, 5, 30, 10, 15)
test_array = np.array([[1, 2], [3, 4]])
scn['test-array'] = xr.DataArray(test_array,
dims=['x', 'y'],
coords={'time': np.datetime64('2018-05-30T10:05:00')},
attrs=dict(start_time=start_time,
end_time=end_time))
with TempFile() as filename:
scn.save_datasets(filename=filename, writer='cf', unlimited_dims=['time'])
with xr.open_dataset(filename) as f:
self.assertSetEqual(f.encoding['unlimited_dims'], {'time'})
[docs] def get_test_attrs(self):
"""Create some dataset attributes for testing purpose.
Returns:
Attributes, encoded attributes, encoded and flattened attributes
"""
attrs = {'name': 'IR_108',
'start_time': datetime(2018, 1, 1, 0),
'end_time': datetime(2018, 1, 1, 0, 15),
'int': 1,
'float': 1.0,
'none': None, # should be dropped
'numpy_int': np.uint8(1),
'numpy_float': np.float32(1),
'numpy_bool': True,
'numpy_void': np.void(0),
'numpy_bytes': np.bytes_('test'),
'numpy_string': np.string_('test'),
'list': [1, 2, np.float64(3)],
'nested_list': ["1", ["2", [3]]],
'bool': True,
'array': np.array([1, 2, 3], dtype='uint8'),
'array_bool': np.array([True, False, True]),
'array_2d': np.array([[1, 2], [3, 4]]),
'array_3d': np.array([[[1, 2], [3, 4]], [[1, 2], [3, 4]]]),
'dict': {'a': 1, 'b': 2},
'nested_dict': {'l1': {'l2': {'l3': np.array([1, 2, 3], dtype='uint8')}}},
'raw_metadata': OrderedDict([
('recarray', np.zeros(3, dtype=[('x', 'i4'), ('y', 'u1')])),
('flag', np.bool_(True)),
('dict', OrderedDict([('a', 1), ('b', np.array([1, 2, 3], dtype='uint8'))]))
])}
encoded = {'name': 'IR_108',
'start_time': '2018-01-01 00:00:00',
'end_time': '2018-01-01 00:15:00',
'int': 1,
'float': 1.0,
'numpy_int': np.uint8(1),
'numpy_float': np.float32(1),
'numpy_bool': 'true',
'numpy_void': '[]',
'numpy_bytes': 'test',
'numpy_string': 'test',
'list': [1, 2, np.float64(3)],
'nested_list': '["1", ["2", [3]]]',
'bool': 'true',
'array': np.array([1, 2, 3], dtype='uint8'),
'array_bool': ['true', 'false', 'true'],
'array_2d': '[[1, 2], [3, 4]]',
'array_3d': '[[[1, 2], [3, 4]], [[1, 2], [3, 4]]]',
'dict': '{"a": 1, "b": 2}',
'nested_dict': '{"l1": {"l2": {"l3": [1, 2, 3]}}}',
'raw_metadata': '{"recarray": [[0, 0], [0, 0], [0, 0]], '
'"flag": "true", "dict": {"a": 1, "b": [1, 2, 3]}}'}
encoded_flat = {'name': 'IR_108',
'start_time': '2018-01-01 00:00:00',
'end_time': '2018-01-01 00:15:00',
'int': 1,
'float': 1.0,
'numpy_int': np.uint8(1),
'numpy_float': np.float32(1),
'numpy_bool': 'true',
'numpy_void': '[]',
'numpy_bytes': 'test',
'numpy_string': 'test',
'list': [1, 2, np.float64(3)],
'nested_list': '["1", ["2", [3]]]',
'bool': 'true',
'array': np.array([1, 2, 3], dtype='uint8'),
'array_bool': ['true', 'false', 'true'],
'array_2d': '[[1, 2], [3, 4]]',
'array_3d': '[[[1, 2], [3, 4]], [[1, 2], [3, 4]]]',
'dict_a': 1,
'dict_b': 2,
'nested_dict_l1_l2_l3': np.array([1, 2, 3], dtype='uint8'),
'raw_metadata_recarray': '[[0, 0], [0, 0], [0, 0]]',
'raw_metadata_flag': 'true',
'raw_metadata_dict_a': 1,
'raw_metadata_dict_b': np.array([1, 2, 3], dtype='uint8')}
return attrs, encoded, encoded_flat
[docs] def assertDictWithArraysEqual(self, d1, d2):
"""Check that dicts containing arrays are equal."""
self.assertSetEqual(set(d1.keys()), set(d2.keys()))
for key, val1 in d1.items():
val2 = d2[key]
if isinstance(val1, np.ndarray):
np.testing.assert_array_equal(val1, val2)
self.assertEqual(val1.dtype, val2.dtype)
else:
self.assertEqual(val1, val2)
if isinstance(val1, (np.floating, np.integer, np.bool_)):
self.assertTrue(isinstance(val2, np.generic))
self.assertEqual(val1.dtype, val2.dtype)
[docs] def test_encode_attrs_nc(self):
"""Test attributes encoding."""
import json
from satpy.writers.cf_writer import encode_attrs_nc
attrs, expected, _ = self.get_test_attrs()
# Test encoding
encoded = encode_attrs_nc(attrs)
self.assertDictWithArraysEqual(expected, encoded)
# Test decoding of json-encoded attributes
raw_md_roundtrip = {'recarray': [[0, 0], [0, 0], [0, 0]],
'flag': 'true',
'dict': {'a': 1, 'b': [1, 2, 3]}}
self.assertDictEqual(json.loads(encoded['raw_metadata']), raw_md_roundtrip)
self.assertListEqual(json.loads(encoded['array_3d']), [[[1, 2], [3, 4]], [[1, 2], [3, 4]]])
self.assertDictEqual(json.loads(encoded['nested_dict']), {"l1": {"l2": {"l3": [1, 2, 3]}}})
self.assertListEqual(json.loads(encoded['nested_list']), ["1", ["2", [3]]])
[docs] def test_da2cf(self):
"""Test the conversion of a DataArray to a CF-compatible DataArray."""
import xarray as xr
from satpy.writers.cf_writer import CFWriter
# Create set of test attributes
attrs, attrs_expected, attrs_expected_flat = self.get_test_attrs()
attrs['area'] = 'some_area'
attrs['prerequisites'] = [make_dsq(name='hej')]
attrs['_satpy_id_name'] = 'myname'
# Adjust expected attributes
expected_prereq = ("DataQuery(name='hej')")
update = {'prerequisites': [expected_prereq], 'long_name': attrs['name']}
attrs_expected.update(update)
attrs_expected_flat.update(update)
attrs_expected.pop('name')
attrs_expected_flat.pop('name')
# Create test data array
arr = xr.DataArray(np.array([[1, 2], [3, 4]]), attrs=attrs, dims=('y', 'x'),
coords={'y': [0, 1], 'x': [1, 2], 'acq_time': ('y', [3, 4])})
# Test conversion to something cf-compliant
res = CFWriter.da2cf(arr)
np.testing.assert_array_equal(res['x'], arr['x'])
np.testing.assert_array_equal(res['y'], arr['y'])
np.testing.assert_array_equal(res['acq_time'], arr['acq_time'])
self.assertDictEqual(res['x'].attrs, {'units': 'm', 'standard_name': 'projection_x_coordinate'})
self.assertDictEqual(res['y'].attrs, {'units': 'm', 'standard_name': 'projection_y_coordinate'})
self.assertDictWithArraysEqual(res.attrs, attrs_expected)
# Test attribute kwargs
res_flat = CFWriter.da2cf(arr, flatten_attrs=True, exclude_attrs=['int'])
attrs_expected_flat.pop('int')
self.assertDictWithArraysEqual(res_flat.attrs, attrs_expected_flat)
[docs] @mock.patch('satpy.writers.cf_writer.CFWriter.__init__', return_value=None)
def test_collect_datasets(self, *mocks):
"""Test collecting CF datasets from a DataArray objects."""
import pyresample.geometry
import xarray as xr
from satpy.writers.cf_writer import CFWriter
geos = pyresample.geometry.AreaDefinition(
area_id='geos',
description='geos',
proj_id='geos',
projection={'proj': 'geos', 'h': 35785831., 'a': 6378169., 'b': 6356583.8},
width=2, height=2,
area_extent=[-1, -1, 1, 1])
# Define test datasets
data = [[1, 2], [3, 4]]
y = [1, 2]
x = [1, 2]
time = [1, 2]
tstart = datetime(2019, 4, 1, 12, 0)
tend = datetime(2019, 4, 1, 12, 15)
datasets = [xr.DataArray(data=data, dims=('y', 'x'), coords={'y': y, 'x': x, 'acq_time': ('y', time)},
attrs={'name': 'var1', 'start_time': tstart, 'end_time': tend, 'area': geos}),
xr.DataArray(data=data, dims=('y', 'x'), coords={'y': y, 'x': x, 'acq_time': ('y', time)},
attrs={'name': 'var2', 'long_name': 'variable 2'})]
# Collect datasets
writer = CFWriter()
datas, start_times, end_times = writer._collect_datasets(datasets, include_lonlats=True)
# Test results
self.assertEqual(len(datas), 3)
self.assertEqual(set(datas.keys()), {'var1', 'var2', 'geos'})
self.assertListEqual(start_times, [None, tstart, None])
self.assertListEqual(end_times, [None, tend, None])
var1 = datas['var1']
var2 = datas['var2']
self.assertEqual(var1.name, 'var1')
self.assertEqual(var1.attrs['grid_mapping'], 'geos')
self.assertEqual(var1.attrs['start_time'], '2019-04-01 12:00:00')
self.assertEqual(var1.attrs['end_time'], '2019-04-01 12:15:00')
self.assertEqual(var1.attrs['long_name'], 'var1')
# variable 2
self.assertNotIn('grid_mapping', var2.attrs)
self.assertEqual(var2.attrs['long_name'], 'variable 2')
[docs] def test_assert_xy_unique(self):
"""Test that the x and y coordinates are unique."""
import xarray as xr
from satpy.writers.cf_writer import assert_xy_unique
dummy = [[1, 2], [3, 4]]
datas = {'a': xr.DataArray(data=dummy, dims=('y', 'x'), coords={'y': [1, 2], 'x': [3, 4]}),
'b': xr.DataArray(data=dummy, dims=('y', 'x'), coords={'y': [1, 2], 'x': [3, 4]}),
'n': xr.DataArray(data=dummy, dims=('v', 'w'), coords={'v': [1, 2], 'w': [3, 4]})}
assert_xy_unique(datas)
datas['c'] = xr.DataArray(data=dummy, dims=('y', 'x'), coords={'y': [1, 3], 'x': [3, 4]})
self.assertRaises(ValueError, assert_xy_unique, datas)
[docs] def test_link_coords(self):
"""Check that coordinates link has been established correctly."""
import numpy as np
import xarray as xr
from satpy.writers.cf_writer import link_coords
data = [[1, 2], [3, 4]]
lon = np.zeros((2, 2))
lon2 = np.zeros((1, 2, 2))
lat = np.ones((2, 2))
datasets = {
'var1': xr.DataArray(data=data, dims=('y', 'x'), attrs={'coordinates': 'lon lat'}),
'var2': xr.DataArray(data=data, dims=('y', 'x')),
'var3': xr.DataArray(data=data, dims=('y', 'x'), attrs={'coordinates': 'lon2 lat'}),
'var4': xr.DataArray(data=data, dims=('y', 'x'), attrs={'coordinates': 'not_exist lon lat'}),
'lon': xr.DataArray(data=lon, dims=('y', 'x')),
'lon2': xr.DataArray(data=lon2, dims=('time', 'y', 'x')),
'lat': xr.DataArray(data=lat, dims=('y', 'x'))
}
link_coords(datasets)
# Check that link has been established correctly and 'coordinate' atrribute has been dropped
self.assertIn('lon', datasets['var1'].coords)
self.assertIn('lat', datasets['var1'].coords)
np.testing.assert_array_equal(datasets['var1']['lon'].data, lon)
np.testing.assert_array_equal(datasets['var1']['lat'].data, lat)
self.assertNotIn('coordinates', datasets['var1'].attrs)
# There should be no link if there was no 'coordinate' attribute
self.assertNotIn('lon', datasets['var2'].coords)
self.assertNotIn('lat', datasets['var2'].coords)
# The non-existant dimension or coordinate should be dropped
self.assertNotIn('time', datasets['var3'].coords)
self.assertNotIn('not_exist', datasets['var4'].coords)
[docs] def test_make_alt_coords_unique(self):
"""Test that created coordinate variables are unique."""
import xarray as xr
from satpy.writers.cf_writer import make_alt_coords_unique
data = [[1, 2], [3, 4]]
y = [1, 2]
x = [1, 2]
time1 = [1, 2]
time2 = [3, 4]
datasets = {'var1': xr.DataArray(data=data,
dims=('y', 'x'),
coords={'y': y, 'x': x, 'acq_time': ('y', time1)}),
'var2': xr.DataArray(data=data,
dims=('y', 'x'),
coords={'y': y, 'x': x, 'acq_time': ('y', time2)})}
# Test that dataset names are prepended to alternative coordinates
res = make_alt_coords_unique(datasets)
np.testing.assert_array_equal(res['var1']['var1_acq_time'], time1)
np.testing.assert_array_equal(res['var2']['var2_acq_time'], time2)
self.assertNotIn('acq_time', res['var1'].coords)
self.assertNotIn('acq_time', res['var2'].coords)
# Make sure nothing else is modified
np.testing.assert_array_equal(res['var1']['x'], x)
np.testing.assert_array_equal(res['var1']['y'], y)
np.testing.assert_array_equal(res['var2']['x'], x)
np.testing.assert_array_equal(res['var2']['y'], y)
# Coords not unique -> Dataset names must be prepended, even if pretty=True
with mock.patch('satpy.writers.cf_writer.warnings.warn') as warn:
res = make_alt_coords_unique(datasets, pretty=True)
warn.assert_called()
np.testing.assert_array_equal(res['var1']['var1_acq_time'], time1)
np.testing.assert_array_equal(res['var2']['var2_acq_time'], time2)
self.assertNotIn('acq_time', res['var1'].coords)
self.assertNotIn('acq_time', res['var2'].coords)
# Coords unique and pretty=True -> Don't modify coordinate names
datasets['var2']['acq_time'] = ('y', time1)
res = make_alt_coords_unique(datasets, pretty=True)
np.testing.assert_array_equal(res['var1']['acq_time'], time1)
np.testing.assert_array_equal(res['var2']['acq_time'], time1)
self.assertNotIn('var1_acq_time', res['var1'].coords)
self.assertNotIn('var2_acq_time', res['var2'].coords)
[docs] def test_area2cf(self):
"""Test the conversion of an area to CF standards."""
import pyresample.geometry
import xarray as xr
from satpy.writers.cf_writer import area2cf
ds_base = xr.DataArray(data=[[1, 2], [3, 4]], dims=('y', 'x'), coords={'y': [1, 2], 'x': [3, 4]},
attrs={'name': 'var1'})
# a) Area Definition and strict=False
geos = pyresample.geometry.AreaDefinition(
area_id='geos',
description='geos',
proj_id='geos',
projection={'proj': 'geos', 'h': 35785831., 'a': 6378169., 'b': 6356583.8},
width=2, height=2,
area_extent=[-1, -1, 1, 1])
ds = ds_base.copy(deep=True)
ds.attrs['area'] = geos
res = area2cf(ds)
self.assertEqual(len(res), 2)
self.assertEqual(res[0].size, 1) # grid mapping variable
self.assertEqual(res[0].name, res[1].attrs['grid_mapping'])
# b) Area Definition and strict=False
ds = ds_base.copy(deep=True)
ds.attrs['area'] = geos
res = area2cf(ds, strict=True)
# same as above
self.assertEqual(len(res), 2)
self.assertEqual(res[0].size, 1) # grid mapping variable
self.assertEqual(res[0].name, res[1].attrs['grid_mapping'])
# but now also have the lon/lats
self.assertIn('longitude', res[1].coords)
self.assertIn('latitude', res[1].coords)
# c) Swath Definition
swath = pyresample.geometry.SwathDefinition(lons=[[1, 1], [2, 2]], lats=[[1, 2], [1, 2]])
ds = ds_base.copy(deep=True)
ds.attrs['area'] = swath
res = area2cf(ds)
self.assertEqual(len(res), 1)
self.assertIn('longitude', res[0].coords)
self.assertIn('latitude', res[0].coords)
self.assertNotIn('grid_mapping', res[0].attrs)
[docs] def test_area2gridmapping(self):
"""Test the conversion from pyresample area object to CF grid mapping."""
import pyresample.geometry
import xarray as xr
from satpy.writers.cf_writer import area2gridmapping
def _gm_matches(gmapping, expected):
"""Assert that all keys in ``expected`` match the values in ``gmapping``."""
for attr_key, attr_val in expected.attrs.items():
test_val = gmapping.attrs[attr_key]
if attr_val is None or isinstance(attr_val, str):
self.assertEqual(test_val, attr_val)
else:
np.testing.assert_almost_equal(test_val, attr_val, decimal=3)
ds_base = xr.DataArray(data=[[1, 2], [3, 4]], dims=('y', 'x'), coords={'y': [1, 2], 'x': [3, 4]},
attrs={'name': 'var1'})
# a) Projection has a corresponding CF representation (e.g. geos)
a = 6378169.
b = 6356583.8
h = 35785831.
geos = pyresample.geometry.AreaDefinition(
area_id='geos',
description='geos',
proj_id='geos',
projection={'proj': 'geos', 'h': h, 'a': a, 'b': b,
'lat_0': 0, 'lon_0': 0},
width=2, height=2,
area_extent=[-1, -1, 1, 1])
geos_expected = xr.DataArray(data=0,
attrs={'perspective_point_height': h,
'latitude_of_projection_origin': 0,
'longitude_of_projection_origin': 0,
'grid_mapping_name': 'geostationary',
'semi_major_axis': a,
'semi_minor_axis': b,
# 'sweep_angle_axis': None,
})
ds = ds_base.copy()
ds.attrs['area'] = geos
new_ds, grid_mapping = area2gridmapping(ds)
if 'sweep_angle_axis' in grid_mapping.attrs:
# older versions of pyproj might not include this
self.assertEqual(grid_mapping.attrs['sweep_angle_axis'], 'y')
self.assertEqual(new_ds.attrs['grid_mapping'], 'geos')
_gm_matches(grid_mapping, geos_expected)
# should not have been modified
self.assertNotIn('grid_mapping', ds.attrs)
# b) Projection does not have a corresponding CF representation (COSMO)
cosmo7 = pyresample.geometry.AreaDefinition(
area_id='cosmo7',
description='cosmo7',
proj_id='cosmo7',
projection={'proj': 'ob_tran', 'ellps': 'WGS84', 'lat_0': 46, 'lon_0': 4.535,
'o_proj': 'stere', 'o_lat_p': 90, 'o_lon_p': -5.465},
width=597, height=510,
area_extent=[-1812933, -1003565, 814056, 1243448]
)
ds = ds_base.copy()
ds.attrs['area'] = cosmo7
new_ds, grid_mapping = area2gridmapping(ds)
self.assertIn('crs_wkt', grid_mapping.attrs)
wkt = grid_mapping.attrs['crs_wkt']
self.assertIn('ELLIPSOID["WGS 84"', wkt)
self.assertIn('PARAMETER["lat_0",46', wkt)
self.assertIn('PARAMETER["lon_0",4.535', wkt)
self.assertIn('PARAMETER["o_lat_p",90', wkt)
self.assertIn('PARAMETER["o_lon_p",-5.465', wkt)
self.assertEqual(new_ds.attrs['grid_mapping'], 'cosmo7')
# c) Projection Transverse Mercator
lat_0 = 36.5
lon_0 = 15.0
tmerc = pyresample.geometry.AreaDefinition(
area_id='tmerc',
description='tmerc',
proj_id='tmerc',
projection={'proj': 'tmerc', 'ellps': 'WGS84', 'lat_0': 36.5, 'lon_0': 15.0},
width=2, height=2,
area_extent=[-1, -1, 1, 1])
tmerc_expected = xr.DataArray(data=0,
attrs={'latitude_of_projection_origin': lat_0,
'longitude_of_central_meridian': lon_0,
'grid_mapping_name': 'transverse_mercator',
'reference_ellipsoid_name': 'WGS 84',
'false_easting': 0.,
'false_northing': 0.,
})
ds = ds_base.copy()
ds.attrs['area'] = tmerc
new_ds, grid_mapping = area2gridmapping(ds)
self.assertEqual(new_ds.attrs['grid_mapping'], 'tmerc')
_gm_matches(grid_mapping, tmerc_expected)
# d) Projection that has a representation but no explicit a/b
h = 35785831.
geos = pyresample.geometry.AreaDefinition(
area_id='geos',
description='geos',
proj_id='geos',
projection={'proj': 'geos', 'h': h, 'datum': 'WGS84', 'ellps': 'GRS80',
'lat_0': 0, 'lon_0': 0},
width=2, height=2,
area_extent=[-1, -1, 1, 1])
geos_expected = xr.DataArray(data=0,
attrs={'perspective_point_height': h,
'latitude_of_projection_origin': 0,
'longitude_of_projection_origin': 0,
'grid_mapping_name': 'geostationary',
# 'semi_major_axis': 6378137.0,
# 'semi_minor_axis': 6356752.314,
# 'sweep_angle_axis': None,
})
ds = ds_base.copy()
ds.attrs['area'] = geos
new_ds, grid_mapping = area2gridmapping(ds)
self.assertEqual(new_ds.attrs['grid_mapping'], 'geos')
_gm_matches(grid_mapping, geos_expected)
# e) oblique Mercator
area = pyresample.geometry.AreaDefinition(
area_id='omerc_otf',
description='On-the-fly omerc area',
proj_id='omerc',
projection={'alpha': '9.02638777018478', 'ellps': 'WGS84', 'gamma': '0', 'k': '1',
'lat_0': '-0.256794486098476', 'lonc': '13.7888658224205',
'proj': 'omerc', 'units': 'm'},
width=2837,
height=5940,
area_extent=[-1460463.0893, 3455291.3877, 1538407.1158, 9615788.8787]
)
omerc_dict = {'azimuth_of_central_line': 9.02638777018478,
'false_easting': 0.,
'false_northing': 0.,
# 'gamma': 0, # this is not CF compliant
'grid_mapping_name': "oblique_mercator",
'latitude_of_projection_origin': -0.256794486098476,
'longitude_of_projection_origin': 13.7888658224205,
# 'prime_meridian_name': "Greenwich",
'reference_ellipsoid_name': "WGS 84"}
omerc_expected = xr.DataArray(data=0, attrs=omerc_dict)
ds = ds_base.copy()
ds.attrs['area'] = area
new_ds, grid_mapping = area2gridmapping(ds)
self.assertEqual(new_ds.attrs['grid_mapping'], 'omerc_otf')
_gm_matches(grid_mapping, omerc_expected)
# f) Projection that has a representation but no explicit a/b
h = 35785831.
geos = pyresample.geometry.AreaDefinition(
area_id='geos',
description='geos',
proj_id='geos',
projection={'proj': 'geos', 'h': h, 'datum': 'WGS84', 'ellps': 'GRS80',
'lat_0': 0, 'lon_0': 0},
width=2, height=2,
area_extent=[-1, -1, 1, 1])
geos_expected = xr.DataArray(data=0,
attrs={'perspective_point_height': h,
'latitude_of_projection_origin': 0,
'longitude_of_projection_origin': 0,
'grid_mapping_name': 'geostationary',
'reference_ellipsoid_name': 'WGS 84',
})
ds = ds_base.copy()
ds.attrs['area'] = geos
new_ds, grid_mapping = area2gridmapping(ds)
self.assertEqual(new_ds.attrs['grid_mapping'], 'geos')
_gm_matches(grid_mapping, geos_expected)
[docs] def test_area2lonlat(self):
"""Test the conversion from areas to lon/lat."""
import dask.array as da
import pyresample.geometry
import xarray as xr
from satpy.writers.cf_writer import area2lonlat
area = pyresample.geometry.AreaDefinition(
'seviri',
'Native SEVIRI grid',
'geos',
"+a=6378169.0 +h=35785831.0 +b=6356583.8 +lon_0=0 +proj=geos",
2, 2,
[-5570248.686685662, -5567248.28340708, 5567248.28340708, 5570248.686685662]
)
lons_ref, lats_ref = area.get_lonlats()
dataarray = xr.DataArray(data=[[1, 2], [3, 4]], dims=('y', 'x'), attrs={'area': area})
res = area2lonlat(dataarray)
# original should be unmodified
self.assertNotIn('longitude', dataarray.coords)
self.assertEqual(set(res.coords), {'longitude', 'latitude'})
lat = res['latitude']
lon = res['longitude']
np.testing.assert_array_equal(lat.data, lats_ref)
np.testing.assert_array_equal(lon.data, lons_ref)
assert {'name': 'latitude', 'standard_name': 'latitude', 'units': 'degrees_north'}.items() <= lat.attrs.items()
assert {'name': 'longitude', 'standard_name': 'longitude', 'units': 'degrees_east'}.items() <= lon.attrs.items()
area = pyresample.geometry.AreaDefinition(
'seviri',
'Native SEVIRI grid',
'geos',
"+a=6378169.0 +h=35785831.0 +b=6356583.8 +lon_0=0 +proj=geos",
10, 10,
[-5570248.686685662, -5567248.28340708, 5567248.28340708, 5570248.686685662]
)
lons_ref, lats_ref = area.get_lonlats()
dataarray = xr.DataArray(data=da.from_array(np.arange(3*10*10).reshape(3, 10, 10), chunks=(1, 5, 5)),
dims=('bands', 'y', 'x'), attrs={'area': area})
res = area2lonlat(dataarray)
# original should be unmodified
self.assertNotIn('longitude', dataarray.coords)
self.assertEqual(set(res.coords), {'longitude', 'latitude'})
lat = res['latitude']
lon = res['longitude']
np.testing.assert_array_equal(lat.data, lats_ref)
np.testing.assert_array_equal(lon.data, lons_ref)
assert {'name': 'latitude', 'standard_name': 'latitude', 'units': 'degrees_north'}.items() <= lat.attrs.items()
assert {'name': 'longitude', 'standard_name': 'longitude', 'units': 'degrees_east'}.items() <= lon.attrs.items()
[docs] def test_load_module_with_old_pyproj(self):
"""Test that cf_writer can still be loaded with pyproj 1.9.6."""
import importlib
import sys
import pyproj # noqa 401
old_version = sys.modules['pyproj'].__version__
sys.modules['pyproj'].__version__ = "1.9.6"
try:
importlib.reload(sys.modules['satpy.writers.cf_writer'])
finally:
# Tear down
sys.modules['pyproj'].__version__ = old_version
importlib.reload(sys.modules['satpy.writers.cf_writer'])
[docs] def test_global_attr_default_history_and_Conventions(self):
"""Test saving global attributes history and Conventions."""
import xarray as xr
from satpy import Scene
scn = Scene()
start_time = datetime(2018, 5, 30, 10, 0)
end_time = datetime(2018, 5, 30, 10, 15)
scn['test-array'] = xr.DataArray([[1, 2, 3]],
dims=('y', 'x'),
attrs=dict(start_time=start_time,
end_time=end_time,
prerequisites=[make_dsq(name='hej')]))
with TempFile() as filename:
scn.save_datasets(filename=filename, writer='cf')
with xr.open_dataset(filename) as f:
self.assertEqual(f.attrs['Conventions'], 'CF-1.7')
self.assertIn('Created by pytroll/satpy on', f.attrs['history'])
[docs] def test_global_attr_history_and_Conventions(self):
"""Test saving global attributes history and Conventions."""
import xarray as xr
from satpy import Scene
scn = Scene()
start_time = datetime(2018, 5, 30, 10, 0)
end_time = datetime(2018, 5, 30, 10, 15)
scn['test-array'] = xr.DataArray([[1, 2, 3]],
dims=('y', 'x'),
attrs=dict(start_time=start_time,
end_time=end_time,
prerequisites=[make_dsq(name='hej')]))
header_attrs = {}
header_attrs['history'] = ('TEST add history',)
header_attrs['Conventions'] = 'CF-1.7, ACDD-1.3'
with TempFile() as filename:
scn.save_datasets(filename=filename, writer='cf', header_attrs=header_attrs)
with xr.open_dataset(filename) as f:
self.assertEqual(f.attrs['Conventions'], 'CF-1.7, ACDD-1.3')
self.assertIn('TEST add history\n', f.attrs['history'])
self.assertIn('Created by pytroll/satpy on', f.attrs['history'])
[docs]def test_lonlat_storage(tmp_path):
"""Test correct storage for area with lon/lat units."""
import xarray as xr
from pyresample import create_area_def
from ..utils import make_fake_scene
scn = make_fake_scene(
{"ketolysis": np.arange(25).reshape(5, 5)},
daskify=True,
area=create_area_def("mavas", 4326, shape=(5, 5),
center=(0, 0), resolution=(1, 1)))
filename = os.fspath(tmp_path / "test.nc")
scn.save_datasets(filename=filename, writer="cf", include_lonlats=False)
with xr.open_dataset(filename) as ds:
assert ds["ketolysis"].attrs["grid_mapping"] == "mavas"
assert ds["mavas"].attrs["grid_mapping_name"] == "latitude_longitude"
assert ds["x"].attrs["units"] == "degrees_east"
assert ds["y"].attrs["units"] == "degrees_north"
assert ds["mavas"].attrs["longitude_of_prime_meridian"] == 0.0
np.testing.assert_allclose(ds["mavas"].attrs["semi_major_axis"], 6378137.0)
np.testing.assert_allclose(ds["mavas"].attrs["inverse_flattening"], 298.257223563)
[docs]def test_da2cf_lonlat():
"""Test correct da2cf encoding for area with lon/lat units."""
import xarray as xr
from pyresample import create_area_def
from satpy.resample import add_crs_xy_coords
from satpy.writers.cf_writer import CFWriter
area = create_area_def("mavas", 4326, shape=(5, 5),
center=(0, 0), resolution=(1, 1))
da = xr.DataArray(
np.arange(25).reshape(5, 5),
dims=("y", "x"),
attrs={"area": area})
da = add_crs_xy_coords(da, area)
new_da = CFWriter.da2cf(da)
assert new_da["x"].attrs["units"] == "degrees_east"
assert new_da["y"].attrs["units"] == "degrees_north"
[docs]def test_is_projected(caplog):
"""Tests for private _is_projected function."""
import xarray as xr
from satpy.writers.cf_writer import CFWriter
# test case with units but no area
da = xr.DataArray(
np.arange(25).reshape(5, 5),
dims=("y", "x"),
coords={"x": xr.DataArray(np.arange(5), dims=("x",), attrs={"units": "m"}),
"y": xr.DataArray(np.arange(5), dims=("y",), attrs={"units": "m"})})
assert CFWriter._is_projected(da)
da = xr.DataArray(
np.arange(25).reshape(5, 5),
dims=("y", "x"),
coords={"x": xr.DataArray(np.arange(5), dims=("x",), attrs={"units": "degrees_east"}),
"y": xr.DataArray(np.arange(5), dims=("y",), attrs={"units": "degrees_north"})})
assert not CFWriter._is_projected(da)
da = xr.DataArray(
np.arange(25).reshape(5, 5),
dims=("y", "x"))
with caplog.at_level(logging.WARNING):
assert CFWriter._is_projected(da)
assert "Failed to tell if data are projected." in caplog.text
[docs]class TestCFWriterData(unittest.TestCase):
"""Test case for CF writer where data arrays are needed."""
[docs] def setUp(self):
"""Create some test data."""
import pyresample.geometry
import xarray as xr
data = [[75, 2], [3, 4]]
y = [1, 2]
x = [1, 2]
geos = pyresample.geometry.AreaDefinition(
area_id='geos',
description='geos',
proj_id='geos',
projection={'proj': 'geos', 'h': 35785831., 'a': 6378169., 'b': 6356583.8},
width=2, height=2,
area_extent=[-1, -1, 1, 1])
self.datasets = {'var1': xr.DataArray(data=data,
dims=('y', 'x'),
coords={'y': y, 'x': x}),
'var2': xr.DataArray(data=data,
dims=('y', 'x'),
coords={'y': y, 'x': x}),
'lat': xr.DataArray(data=data,
dims=('y', 'x'),
coords={'y': y, 'x': x}),
'lon': xr.DataArray(data=data,
dims=('y', 'x'),
coords={'y': y, 'x': x})}
self.datasets['lat'].attrs['standard_name'] = 'latitude'
self.datasets['var1'].attrs['standard_name'] = 'dummy'
self.datasets['var2'].attrs['standard_name'] = 'dummy'
self.datasets['var2'].attrs['area'] = geos
self.datasets['var1'].attrs['area'] = geos
self.datasets['lat'].attrs['name'] = 'lat'
self.datasets['var1'].attrs['name'] = 'var1'
self.datasets['var2'].attrs['name'] = 'var2'
self.datasets['lon'].attrs['name'] = 'lon'
[docs] def test_dataset_is_projection_coords(self):
"""Test the dataset_is_projection_coords function."""
from satpy.writers.cf_writer import dataset_is_projection_coords
self.assertTrue(dataset_is_projection_coords(self.datasets['lat']))
self.assertFalse(dataset_is_projection_coords(self.datasets['var1']))
[docs] def test_has_projection_coords(self):
"""Test the has_projection_coords function."""
from satpy.writers.cf_writer import has_projection_coords
self.assertTrue(has_projection_coords(self.datasets))
self.datasets['lat'].attrs['standard_name'] = 'dummy'
self.assertFalse(has_projection_coords(self.datasets))
[docs] @mock.patch('satpy.writers.cf_writer.CFWriter.__init__', return_value=None)
def test_collect_datasets_with_latitude_named_lat(self, *mocks):
"""Test collecting CF datasets with latitude named lat."""
from operator import getitem
from satpy.writers.cf_writer import CFWriter
self.datasets_list = [self.datasets[key] for key in self.datasets]
self.datasets_list_no_latlon = [self.datasets[key] for key in ['var1', 'var2']]
# Collect datasets
writer = CFWriter()
datas, start_times, end_times = writer._collect_datasets(self.datasets_list, include_lonlats=True)
datas2, start_times, end_times = writer._collect_datasets(self.datasets_list_no_latlon, include_lonlats=True)
# Test results
self.assertEqual(len(datas), 5)
self.assertEqual(set(datas.keys()), {'var1', 'var2', 'lon', 'lat', 'geos'})
self.assertRaises(KeyError, getitem, datas['var1'], 'latitude')
self.assertRaises(KeyError, getitem, datas['var1'], 'longitude')
self.assertEqual(datas2['var1']['latitude'].attrs['name'], 'latitude')
self.assertEqual(datas2['var1']['longitude'].attrs['name'], 'longitude')
[docs]class EncodingUpdateTest(unittest.TestCase):
"""Test update of netCDF encoding."""
[docs] def setUp(self):
"""Create fake data for testing."""
import xarray as xr
self.ds = xr.Dataset({'foo': (('y', 'x'), [[1, 2], [3, 4]]),
'bar': (('y', 'x'), [[3, 4], [5, 6]])},
coords={'y': [1, 2],
'x': [3, 4],
'lon': (('y', 'x'), [[7, 8], [9, 10]])})
self.ds_digit = xr.Dataset({'CHANNEL_1': (('y', 'x'), [[1, 2], [3, 4]]),
'CHANNEL_2': (('y', 'x'), [[3, 4], [5, 6]])},
coords={'y': [1, 2],
'x': [3, 4],
'lon': (('y', 'x'), [[7, 8], [9, 10]])})
[docs] def test_dataset_name_digit(self):
"""Test data with dataset name staring with a digit."""
from satpy.writers.cf_writer import update_encoding
# Dataset with name staring with digit
ds = self.ds_digit
kwargs = {'encoding': {'1': {'dtype': 'float32'},
'2': {'dtype': 'float32'}},
'other': 'kwargs'}
enc, other_kwargs = update_encoding(ds, kwargs, numeric_name_prefix='CHANNEL_')
self.assertDictEqual(enc, {'y': {'_FillValue': None},
'x': {'_FillValue': None},
'CHANNEL_1': {'dtype': 'float32'},
'CHANNEL_2': {'dtype': 'float32'}})
self.assertDictEqual(other_kwargs, {'other': 'kwargs'})
[docs] def test_without_time(self):
"""Test data with no time dimension."""
from satpy.writers.cf_writer import update_encoding
# Without time dimension
ds = self.ds.chunk(2)
kwargs = {'encoding': {'bar': {'chunksizes': (1, 1)}},
'other': 'kwargs'}
enc, other_kwargs = update_encoding(ds, kwargs)
self.assertDictEqual(enc, {'y': {'_FillValue': None},
'x': {'_FillValue': None},
'lon': {'chunksizes': (2, 2)},
'foo': {'chunksizes': (2, 2)},
'bar': {'chunksizes': (1, 1)}})
self.assertDictEqual(other_kwargs, {'other': 'kwargs'})
# Chunksize may not exceed shape
ds = self.ds.chunk(8)
kwargs = {'encoding': {}, 'other': 'kwargs'}
enc, other_kwargs = update_encoding(ds, kwargs)
self.assertDictEqual(enc, {'y': {'_FillValue': None},
'x': {'_FillValue': None},
'lon': {'chunksizes': (2, 2)},
'foo': {'chunksizes': (2, 2)},
'bar': {'chunksizes': (2, 2)}})
[docs] def test_with_time(self):
"""Test data with a time dimension."""
from satpy.writers.cf_writer import update_encoding
# With time dimension
ds = self.ds.chunk(8).expand_dims({'time': [datetime(2009, 7, 1, 12, 15)]})
kwargs = {'encoding': {'bar': {'chunksizes': (1, 1, 1)}},
'other': 'kwargs'}
enc, other_kwargs = update_encoding(ds, kwargs)
self.assertDictEqual(enc, {'y': {'_FillValue': None},
'x': {'_FillValue': None},
'lon': {'chunksizes': (2, 2)},
'foo': {'chunksizes': (1, 2, 2)},
'bar': {'chunksizes': (1, 1, 1)},
'time': {'_FillValue': None,
'calendar': 'proleptic_gregorian',
'units': 'days since 2009-07-01 12:15:00'},
'time_bnds': {'_FillValue': None,
'calendar': 'proleptic_gregorian',
'units': 'days since 2009-07-01 12:15:00'}})
# User-defined encoding may not be altered
self.assertDictEqual(kwargs['encoding'], {'bar': {'chunksizes': (1, 1, 1)}})
[docs]class TestEncodingKwarg:
"""Test CF writer with 'encoding' keyword argument."""
[docs] @pytest.fixture
def scene(self):
"""Create a fake scene."""
scn = Scene()
attrs = {
"start_time": datetime(2018, 5, 30, 10, 0),
"end_time": datetime(2018, 5, 30, 10, 15)
}
scn['test-array'] = xr.DataArray([1., 2, 3], attrs=attrs)
return scn
[docs] @pytest.fixture(params=[True, False])
def compression_on(self, request):
"""Get compression options."""
return request.param
[docs] @pytest.fixture
def encoding(self, compression_on):
"""Get encoding."""
enc = {
'test-array': {
'dtype': 'int8',
'scale_factor': 0.1,
'add_offset': 0.0,
'_FillValue': 3,
}
}
if compression_on:
comp_params = _get_compression_params(complevel=7)
enc["test-array"].update(comp_params)
return enc
[docs] @pytest.fixture
def filename(self, tmp_path):
"""Get output filename."""
return str(tmp_path / "test.nc")
[docs] @pytest.fixture
def complevel_exp(self, compression_on):
"""Get expected compression level."""
if compression_on:
return 7
return 0
[docs] @pytest.fixture
def expected(self, complevel_exp):
"""Get expectated file contents."""
return {
"data": [10, 20, 30],
"scale_factor": 0.1,
"fill_value": 3,
"dtype": np.int8,
"complevel": complevel_exp
}
[docs] def test_encoding_kwarg(self, scene, encoding, filename, expected):
"""Test 'encoding' keyword argument."""
scene.save_datasets(filename=filename, encoding=encoding, writer='cf')
self._assert_encoding_as_expected(filename, expected)
def _assert_encoding_as_expected(self, filename, expected):
with xr.open_dataset(filename, mask_and_scale=False) as f:
np.testing.assert_array_equal(f['test-array'][:], expected["data"])
assert f['test-array'].attrs['scale_factor'] == expected["scale_factor"]
assert f['test-array'].attrs['_FillValue'] == expected["fill_value"]
assert f['test-array'].dtype == expected["dtype"]
assert f["test-array"].encoding["complevel"] == expected["complevel"]
[docs] def test_warning_if_backends_dont_match(self, scene, filename, monkeypatch):
"""Test warning if backends don't match."""
import netCDF4
with monkeypatch.context() as m:
m.setattr(netCDF4, "__version__", "1.5.0")
m.setattr(netCDF4, "__netcdf4libversion__", "4.9.1")
with pytest.warns(UserWarning, match=r"Backend version mismatch"):
scene.save_datasets(filename=filename, writer="cf")
[docs] def test_no_warning_if_backends_match(self, scene, filename, monkeypatch):
"""Make sure no warning is issued if backends match."""
import netCDF4
with monkeypatch.context() as m:
m.setattr(netCDF4, "__version__", "1.6.0")
m.setattr(netCDF4, "__netcdf4libversion__", "4.9.0")
m.setattr(xr, "__version__", "2022.12.0")
with warnings.catch_warnings():
scene.save_datasets(filename=filename, writer="cf")
warnings.simplefilter("error")
[docs]class TestEncodingAttribute(TestEncodingKwarg):
"""Test CF writer with 'encoding' dataset attribute."""
[docs] @pytest.fixture
def scene_with_encoding(self, scene, encoding):
"""Create scene with a dataset providing the 'encoding' attribute."""
scene["test-array"].encoding = encoding["test-array"]
return scene
[docs] def test_encoding_attribute(self, scene_with_encoding, filename, expected):
"""Test 'encoding' dataset attribute."""
scene_with_encoding.save_datasets(filename=filename, writer='cf')
self._assert_encoding_as_expected(filename, expected)
def _get_compression_params(complevel):
params = {"complevel": complevel}
if _should_use_compression_keyword():
params["compression"] = "zlib"
else:
params["zlib"] = True
return params
def _should_use_compression_keyword():
# xarray currently ignores the "compression" keyword, see
# https://github.com/pydata/xarray/issues/7388. There's already an open
# PR, so we assume that this will be fixed in the next minor release
# (current release is 2023.02). If not, tests will fail and remind us.
versions = _get_backend_versions()
return (
versions["libnetcdf"] >= Version("4.9.0") and
versions["xarray"] >= Version("2023.04")
)