#!/usr/bin/env python
# -*- coding: utf-8 -*-
# Copyright (c) 2018, 2022 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 VIIRS compositors."""
from datetime import datetime
import dask.array as da
import numpy as np
import pytest
import xarray as xr
from pyresample.geometry import AreaDefinition
[docs]
class TestVIIRSComposites:
"""Test various VIIRS-specific composites."""
[docs]
@pytest.fixture()
def area(self):
"""Return fake area for use with DNB tests."""
rows = 5
cols = 10
area = AreaDefinition(
"test", "test", "test",
{"proj": "eqc", "lon_0": 0.0,
"lat_0": 0.0},
cols, rows,
(-20037508.34, -10018754.17, 20037508.34, 10018754.17))
return area
[docs]
@pytest.fixture()
def dnb(self, area):
"""Return fake channel 1 data for DNB tests."""
dnb = np.zeros(area.shape) + 0.25
dnb[3, :] += 0.25
dnb[4:, :] += 0.5
dnb = da.from_array(dnb, chunks=25)
c01 = xr.DataArray(dnb,
dims=("y", "x"),
attrs={"name": "DNB", "area": area,
"start_time": datetime(2020, 1, 1, 12, 0, 0)})
return c01
[docs]
@pytest.fixture()
def sza(self, area):
"""Return fake sza dataset for DNB tests."""
# data changes by row, sza changes by col for testing
sza = np.zeros(area.shape) + 70.0
sza[:, 3] += 20.0
sza[:, 4:] += 45.0
sza = da.from_array(sza, chunks=25)
c02 = xr.DataArray(sza,
dims=("y", "x"),
attrs={"name": "solar_zenith_angle", "area": area,
"start_time": datetime(2020, 1, 1, 12, 0, 0)})
return c02
[docs]
@pytest.fixture()
def lza(self, area):
"""Return fake lunal zenith angle dataset for DNB tests."""
lza = np.zeros(area.shape) + 70.0
lza[:, 3] += 20.0
lza[:, 4:] += 45.0
lza = da.from_array(lza, chunks=25)
c03 = xr.DataArray(lza,
dims=("y", "x"),
attrs={"name": "lunar_zenith_angle", "area": area,
"start_time": datetime(2020, 1, 1, 12, 0, 0)
})
return c03
[docs]
def test_load_composite_yaml(self):
"""Test loading the yaml for this sensor."""
from satpy.composites.config_loader import load_compositor_configs_for_sensors
load_compositor_configs_for_sensors(["viirs"])
[docs]
def test_histogram_dnb(self, dnb, sza):
"""Test the 'histogram_dnb' compositor."""
from satpy.composites.viirs import HistogramDNB
comp = HistogramDNB("histogram_dnb", prerequisites=("dnb",),
standard_name="toa_outgoing_radiance_per_"
"unit_wavelength")
res = comp((dnb, sza))
assert isinstance(res, xr.DataArray)
assert isinstance(res.data, da.Array)
assert res.attrs["name"] == "histogram_dnb"
assert res.attrs["standard_name"] == "equalized_radiance"
data = res.compute()
unique_values = np.unique(data)
np.testing.assert_allclose(unique_values, [0.5994, 0.7992, 0.999], rtol=1e-3)
[docs]
def test_adaptive_dnb(self, dnb, sza):
"""Test the 'adaptive_dnb' compositor."""
from satpy.composites.viirs import AdaptiveDNB
comp = AdaptiveDNB("adaptive_dnb", prerequisites=("dnb",),
standard_name="toa_outgoing_radiance_per_"
"unit_wavelength")
res = comp((dnb, sza))
assert isinstance(res, xr.DataArray)
assert isinstance(res.data, da.Array)
assert res.attrs["name"] == "adaptive_dnb"
assert res.attrs["standard_name"] == "equalized_radiance"
data = res.compute()
np.testing.assert_allclose(data.data, 0.999, rtol=1e-4)
[docs]
def test_hncc_dnb(self, area, dnb, sza, lza):
"""Test the 'hncc_dnb' compositor."""
from satpy.composites.viirs import NCCZinke
comp = NCCZinke("hncc_dnb", prerequisites=("dnb",),
standard_name="toa_outgoing_radiance_per_"
"unit_wavelength")
mif = xr.DataArray(da.zeros((5,), chunks=5) + 0.1,
dims=("y",),
attrs={"name": "moon_illumination_fraction", "area": area})
res = comp((dnb, sza, lza, mif))
assert isinstance(res, xr.DataArray)
assert isinstance(res.data, da.Array)
assert res.attrs["name"] == "hncc_dnb"
assert res.attrs["standard_name"] == "ncc_radiance"
data = res.compute()
unique = np.unique(data)
np.testing.assert_allclose(
unique, [3.48479712e-04, 6.96955799e-04, 1.04543189e-03, 4.75394738e-03,
9.50784532e-03, 1.42617433e-02, 1.50001560e+03, 3.00001560e+03,
4.50001560e+03])
with pytest.raises(ValueError, match="Expected .*, got 2"):
comp((dnb, sza))
[docs]
def test_hncc_dnb_nomoonpha(self, area, dnb, sza, lza):
"""Test the 'hncc_dnb' compositor when no moon phase data is provided."""
from satpy.composites.viirs import NCCZinke
comp = NCCZinke("hncc_dnb", prerequisites=("dnb",),
standard_name="toa_outgoing_radiance_per_"
"unit_wavelength")
res = comp((dnb, sza, lza))
assert isinstance(res, xr.DataArray)
assert isinstance(res.data, da.Array)
assert res.attrs["name"] == "hncc_dnb"
assert res.attrs["standard_name"] == "ncc_radiance"
data = res.compute()
unique = np.unique(data)
np.testing.assert_allclose(
unique, [3.48479672e-04, 6.96955721e-04, 1.04543177e-03, 4.75394684e-03,
9.50784425e-03, 1.42617416e-02, 1.50001543e+03, 3.00001526e+03,
4.50001509e+03])
[docs]
@pytest.mark.parametrize("dnb_units", ["W m-2 sr-1", "W cm-2 sr-1"])
@pytest.mark.parametrize("saturation_correction", [False, True])
def test_erf_dnb(self, dnb_units, saturation_correction, area, sza, lza):
"""Test the 'dynamic_dnb' or ERF DNB compositor."""
from satpy.composites.viirs import ERFDNB
comp = ERFDNB("dynamic_dnb", prerequisites=("dnb",),
saturation_correction=saturation_correction,
standard_name="toa_outgoing_radiance_per_"
"unit_wavelength")
# dnb is different from in the other tests, so don't use the fixture
# here
dnb = np.zeros(area.shape) + 0.25
cols = area.shape[1]
dnb[2, :cols // 2] = np.nan
dnb[3, :] += 0.25
dnb[4:, :] += 0.5
if dnb_units == "W cm-2 sr-1":
dnb /= 10000.0
dnb = da.from_array(dnb, chunks=25)
c01 = xr.DataArray(dnb,
dims=("y", "x"),
attrs={"name": "DNB", "area": area, "units": dnb_units})
mif = xr.DataArray(da.zeros((5,), chunks=5) + 0.1,
dims=("y",),
attrs={"name": "moon_illumination_fraction", "area": area})
res = comp((c01, sza, lza, mif))
assert isinstance(res, xr.DataArray)
assert isinstance(res.data, da.Array)
assert res.attrs["name"] == "dynamic_dnb"
assert res.attrs["standard_name"] == "equalized_radiance"
data = res.compute()
unique = np.unique(data)
assert np.isnan(unique).any()
nonnan_unique = unique[~np.isnan(unique)]
if saturation_correction:
exp_unique = [0.000000e+00, 3.978305e-04, 6.500003e-04,
8.286927e-04, 5.628335e-01, 7.959671e-01,
9.748567e-01]
else:
exp_unique = [0.00000000e+00, 1.00446703e-01, 1.64116082e-01,
2.09233451e-01, 1.43916324e+02, 2.03528498e+02,
2.49270516e+02]
np.testing.assert_allclose(nonnan_unique, exp_unique)
[docs]
def test_snow_age(self, area):
"""Test the 'snow_age' compositor."""
from satpy.composites.viirs import SnowAge
projectables = tuple(
xr.DataArray(
da.from_array(np.full(area.shape, 5.*i), chunks=5),
dims=("y", "x"),
attrs={"name": f"M0{i:d}",
"calibration": "reflectance",
"units": "%"})
for i in range(7, 12))
comp = SnowAge(
"snow_age",
prerequisites=("M07", "M08", "M09", "M10", "M11",),
standard_name="snow_age")
res = comp(projectables)
assert isinstance(res, xr.DataArray)
assert isinstance(res.data, da.Array)
assert res.attrs["name"] == "snow_age"
assert "units" not in res.attrs