def get_dataset(self, key, info):
if self._data is None:
self.read()
if key.name in ['latitude', 'longitude']:
lons, lats = self.get_lonlats()
if key.name == 'latitude':
return Projectable(lats, id=key)
else:
return Projectable(lons, id=key)
avhrr_channel_index = {'1': 0,
'2': 1,
'3a': 2,
'3b': 2,
'4': 3,
'5': 4}
index = avhrr_channel_index[key.name]
mask = False
if key.name in ['3a', '3b'] and self._is3b is None:
ch3a = bfield(self._data["id"]["id"], 10)
self._is3b = np.logical_not(ch3a)
if key.name == '3a':
mask = np.tile(self._is3b, (1, 2048))
elif key.name == '3b':
mask = np.tile(np.logical_not(self._is3b), (1, 2048))
data = self._data["image_data"][:, :, index]
if key.calibration == 'counts':
return Projectable(data,
mask=mask,
area=self.get_lonlats(),
units='1')
pg_spacecraft = ''.join(self.platform_name.split()).lower()
jdays = (np.datetime64(self.start_time) - np.datetime64(str(
self.year) + '-01-01T00:00:00Z')) / np.timedelta64(1, 'D')
if index < 2 or key.name == '3a':
data = calibrate_solar(data, index, self.year, jdays,
pg_spacecraft)
units = '%'
if index > 2 or key.name == '3b':
if self.times is None:
self.times = time_seconds(self._data["timecode"], self.year)
line_numbers = (
np.round((self.times - self.times[-1]) /
np.timedelta64(166666667, 'ns'))).astype(np.int)
line_numbers -= line_numbers[0]
if self.prt is None:
self.prt, self.ict, self.space = self.get_telemetry()
chan = index + 1
data = calibrate_thermal(data, self.prt, self.ict[:, chan - 3],
self.space[:, chan - 3], line_numbers,
chan, pg_spacecraft)
units = 'K'
# TODO: check if entirely masked before returning
return Projectable(data, mask=mask, units=units)
def get_calibrated_channels(self):
channels = self.get_counts()
self.get_times()
year = self.times[0].year
delta = self.times[0].date() - datetime.date(year, 1, 1)
jday = delta.days + 1
# Earth-Sun distance correction factor
corr = 1.0 - 0.0334 * np.cos(2.0 * np.pi * (jday - 2) / 365.25)
# how many reflective channels are there ?
tot_ref = channels.shape[2] - 3
channels[:, :, 0:tot_ref] = calibrate_solar(channels[:, :, 0:tot_ref],
np.arange(tot_ref),
year, jday,
self.spacecraft_name,
corr)
prt, ict, space = self.get_telemetry()
for chan in [3, 4, 5]:
channels[:, :, chan - 6] = calibrate_thermal(
channels[:, :, chan - 6],
prt,
ict[:, chan - 3],
space[:, chan - 3],
self.scans["scan_line_number"],
chan,
self.spacecraft_name)
return channels
def get_dataset(self, key, info):
if self._data is None:
self.read()
if key.name in ['latitude', 'longitude']:
lons, lats = self.get_lonlats()
if key.name == 'latitude':
return Dataset(lats, id=key)
else:
return Dataset(lons, id=key)
avhrr_channel_index = {
'1': 0,
'2': 1,
'3a': 2,
'3b': 2,
'4': 3,
'5': 4
}
index = avhrr_channel_index[key.name]
mask = False
if key.name in ['3a', '3b'] and self._is3b is None:
ch3a = bfield(self._data["id"]["id"], 10)
self._is3b = np.logical_not(ch3a)
if key.name == '3a':
mask = np.tile(self._is3b, (1, 2048))
elif key.name == '3b':
mask = np.tile(np.logical_not(self._is3b), (1, 2048))
data = self._data["image_data"][:, :, index]
if key.calibration == 'counts':
return Dataset(data, mask=mask, area=self.get_lonlats(), units='1')
pg_spacecraft = ''.join(self.platform_name.split()).lower()
jdays = (np.datetime64(self.start_time) -
np.datetime64(str(self.year) +
'-01-01T00:00:00Z')) / np.timedelta64(1, 'D')
if index < 2 or key.name == '3a':
data = calibrate_solar(data, index, self.year, jdays,
pg_spacecraft)
units = '%'
if index > 2 or key.name == '3b':
if self.times is None:
self.times = time_seconds(self._data["timecode"], self.year)
line_numbers = (np.round(
(self.times - self.times[-1]) /
np.timedelta64(166666667, 'ns'))).astype(np.int)
line_numbers -= line_numbers[0]
if self.prt is None:
self.prt, self.ict, self.space = self.get_telemetry()
chan = index + 1
data = calibrate_thermal(data, self.prt, self.ict[:, chan - 3],
self.space[:, chan - 3], line_numbers,
chan, pg_spacecraft)
units = 'K'
# TODO: check if entirely masked before returning
return Dataset(data, mask=mask, units=units)
def test_calibration_vis(self):
counts = np.array([[
0, 0, 0, 0, 0, 512, 512, 512, 512, 512, 1023, 1023, 1023, 1023,
1023
],
[
41, 41, 41, 41, 41, 150, 150, 150, 150, 150,
700, 700, 700, 700, 700
]])
year = 1997
jday = 196
spacecraft_id = "noaa14"
channel3_switch = 0
corr = 1
number_of_data_records = 2
channel = 0
ref1 = calibrate_solar(counts[:, channel::5], channel, year, jday,
spacecraft_id, corr)
channel = 1
ref2 = calibrate_solar(counts[:, channel::5], channel, year, jday,
spacecraft_id, corr)
channel = 2
data = np.ma.array(counts[:, channel::5], mask=True)
ref3 = calibrate_solar(data, channel, year, jday, spacecraft_id, corr)
expected = (np.array([[-5.34164812, 61.36381128, 127.93898657],
[0., 14.20096694, 85.85722215]]),
np.array([[-6.49947747, 74.66472898, 155.67041159],
[0., 17.27909864, 104.46721104]]),
np.array([[-32001., -32001., -32001.],
[-32001., -32001., -32001.]]))
self.assertTrue(np.allclose(ref1, expected[0]))
self.assertTrue(np.allclose(ref2, expected[1]))
self.assertTrue(np.allclose(ref3.filled(-32001), expected[2]))
def test_calibration_vis(self):
counts = np.array([[0, 0, 0, 0, 0,
512, 512, 512, 512, 512,
1023, 1023, 1023, 1023, 1023],
[41, 41, 41, 41, 41,
150, 150, 150, 150, 150,
700, 700, 700, 700, 700]])
year = 2010
jday = 1
spacecraft_id = "noaa19"
channel3_switch = 0
corr = 1
number_of_data_records = 2
channel = 0
ref1 = calibrate_solar(counts[:, channel::5], channel, year, jday,
spacecraft_id, corr)
channel = 1
ref2 = calibrate_solar(counts[:, channel::5], channel, year, jday,
spacecraft_id, corr)
channel = 2
data = np.ma.array(counts[:, channel::5], mask=True)
ref3 = calibrate_solar(data, channel, year, jday,
spacecraft_id, corr)
expected = (np.array([[-2.13225247, 27.71598482, 111.96193939],
[0.12090091, 6.11099162, 58.71058259]]),
np.array([[-2.41276542e+00, 3.06897170e+01, 1.25011705e+02],
[1.23731560e-01, 6.86710159e+00, 6.53913486e+01]]),
np.ones((2, 3)) * -32001)
self.assertTrue(np.allclose(ref1, expected[0]))
self.assertTrue(np.allclose(ref2, expected[1]))
self.assertTrue(np.allclose(ref3.filled(-32001), expected[2]))