def test_same_units(self):
"""Test plugin produces the correct weights when the parameters for
the triangle are in the same units as the input cube's coordinate"""
WeightsClass = ChooseDefaultWeightsTriangular(2, 1, units=self.units)
weights = WeightsClass.process(self.cube, self.coord_name)
expected_weights = np.array([0.33333333, 0.66666667])
self.assertArrayAlmostEqual(weights, expected_weights)
def test_unconvertable_units(self):
""""Test plugin produces the correct weights when the parameters for
the triangle cannot be converted to the same units as the
coordinate"""
WeightsClass = ChooseDefaultWeightsTriangular(7200, 3600, units="m")
message = r"Unable to convert from 'Unit\('m'\)' to 'Unit\('hours'\)'"
with self.assertRaisesRegexp(ValueError, message):
WeightsClass.process(self.cube, self.coord_name)
def test_basic(self):
"""Test that the function returns a numpy array.
Also check that the length of the weights is correct and they add
up to 1.0"""
TriangularWeightsClass = ChooseDefaultWeightsTriangular(3, 5)
coord_vals = np.arange(15)
weights = TriangularWeightsClass.triangular_weights(coord_vals)
self.assertIsInstance(weights, np.ndarray)
self.assertEqual(len(weights), len(coord_vals))
self.assertEqual(weights.sum(), 1.0)
def test_different_units(self):
""""Test plugin produces the correct weights when the parameters for
the triangle are in different units to the input cube's
coordinate"""
WeightsClass = ChooseDefaultWeightsTriangular(7200,
3600,
units="seconds")
weights = WeightsClass.process(self.cube, self.coord_name)
expected_weights = np.array([0.33333333, 0.66666667])
self.assertArrayAlmostEqual(weights, expected_weights)
def test_basic_weights(self):
"""Test that the function returns the correct triangular weights in a
simple case"""
TriangularWeightsClass = ChooseDefaultWeightsTriangular(3, 5)
coord_vals = np.arange(15)
weights = TriangularWeightsClass.triangular_weights(coord_vals)
expected_weights = np.array([
0., 0., 0., 0.11111111, 0.22222222, 0.33333333, 0.22222222,
0.11111111, 0., 0., 0., 0., 0., 0., 0.
])
self.assertArrayAlmostEqual(weights, expected_weights)
def test_non_integer_width(self):
"""Test when the width of the triangle does not fall on a grid point.
This only affects the slope of the triangle slightly."""
TriangularWeightsClass = ChooseDefaultWeightsTriangular(3.5, 5)
coord_vals = np.arange(15)
weights = TriangularWeightsClass.triangular_weights(coord_vals)
expected_weights = np.array([
0., 0., 0.04, 0.12, 0.2, 0.28, 0.2, 0.12, 0.04, 0., 0., 0., 0., 0.,
0.
])
self.assertArrayAlmostEqual(weights, expected_weights)
def test_midpoint_at_edge(self):
"""Test that the correct triangular weights are returned for a case
where the midpoint is close to the end of the input coordinate.
In this case the triangle is cut off at the end of the coordinate"""
TriangularWeightsClass = ChooseDefaultWeightsTriangular(3, 1)
coord_vals = np.arange(15)
weights = TriangularWeightsClass.triangular_weights(coord_vals)
expected_weights = np.array([
0.25, 0.375, 0.25, 0.125, 0., 0., 0., 0., 0., 0., 0., 0., 0., 0.,
0.
])
self.assertArrayAlmostEqual(weights, expected_weights)
def test_non_integer_midpoint(self):
"""Test the case where the midpoint of the triangle is not a point in
the input coordinate.
In this case we do not sample the peak of the triangle."""
TriangularWeightsClass = ChooseDefaultWeightsTriangular(2, 3.5)
coord_vals = np.arange(15)
weights = TriangularWeightsClass.triangular_weights(coord_vals)
expected_weights = np.array([
0., 0., 0.125, 0.375, 0.375, 0.125, 0., 0., 0., 0., 0., 0., 0., 0.,
0.
])
self.assertArrayAlmostEqual(weights, expected_weights)
def test_large_width(self):
"""Test the case where the width of the triangle is larger than the
coordinate input.
In this case all the weights are non-zero but still form the
shape of a triangle."""
TriangularWeightsClass = ChooseDefaultWeightsTriangular(10, 5)
coord_vals = np.arange(15)
weights = TriangularWeightsClass.triangular_weights(coord_vals)
expected_weights = np.array([
0.055556, 0.066667, 0.077778, 0.088889, 0.1, 0.111111, 0.1,
0.088889, 0.077778, 0.066667, 0.055556, 0.044444, 0.033333,
0.022222, 0.011111
])
self.assertArrayAlmostEqual(weights, expected_weights)
def test_unevenly_spaced_coord(self):
"""Test the case where the input coordinate is not equally spaced.
This represents the case where the data changes to 3 hourly. In this
case the weights are assigned according to the value in the
coordinate."""
TriangularWeightsClass = ChooseDefaultWeightsTriangular(5, 8)
coord_vals = np.arange(10)
coord_vals = np.append(coord_vals, [12, 15, 18, 21, 24])
weights = TriangularWeightsClass.triangular_weights(coord_vals)
expected_weights = np.array([
0., 0., 0., 0., 0.05, 0.1, 0.15, 0.2, 0.25, 0.2, 0.05, 0., 0., 0.,
0.
])
self.assertArrayAlmostEqual(weights, expected_weights)
def test_cf_unit_input(self):
"""Test the case where an instance of cf_units.Unit is passed in"""
units = cf_units.Unit("hour")
WeightsClass = ChooseDefaultWeightsTriangular(5, 8, units=units)
expected_width = 5
expected_midpoint = 8
expected_unit = units
self.assertEqual(WeightsClass.width, expected_width)
self.assertEqual(WeightsClass.midpoint, expected_midpoint)
self.assertEqual(WeightsClass.parameters_units, expected_unit)
def test_string_input(self):
"""Test the case where a string is passed and gets converted to a
cf_units.Unit instance"""
units = "hour"
WeightsClass = ChooseDefaultWeightsTriangular(5, 8, units=units)
expected_width = 5
expected_midpoint = 8
expected_unit = cf_units.Unit("hour")
self.assertEqual(WeightsClass.width, expected_width)
self.assertEqual(WeightsClass.midpoint, expected_midpoint)
self.assertEqual(WeightsClass.parameters_units, expected_unit)
def test_basic(self):
"""Test the repr function formats the arguments correctly"""
TriangularWeightsClass = ChooseDefaultWeightsTriangular(3, 5)
result = str(TriangularWeightsClass)
expected = "<ChooseDefaultTriangularWeights width= 3.0, midpoint= 5.0>"
self.assertEqual(result, expected)