def test_spherical_default_supported(self):
cs_by_shape = {
0: icoord_systems.GeogCS(6367470),
6: icoord_systems.GeogCS(6371229)
}
for shape, expected in cs_by_shape.items():
result = ellipsoid(shape, MDI, MDI, MDI)
self.assertEqual(result, expected)
def test_netcdf_save_gridmapping(self):
# Test saving CF-netCDF from a cubelist with various grid mappings.
c1 = self.cubell
c2 = self.cubell.copy()
c3 = self.cubell.copy()
coord_system = icoord_systems.GeogCS(6371229)
coord_system2 = icoord_systems.GeogCS(6371228)
coord_system3 = icoord_systems.RotatedGeogCS(30, 30)
c1.add_dim_coord(
iris.coords.DimCoord(np.arange(1, 3),
'latitude',
long_name='1',
units='degrees',
coord_system=coord_system), 1)
c1.add_dim_coord(
iris.coords.DimCoord(np.arange(1, 3),
'longitude',
long_name='1',
units='degrees',
coord_system=coord_system), 0)
c2.add_dim_coord(
iris.coords.DimCoord(np.arange(1, 3),
'latitude',
long_name='2',
units='degrees',
coord_system=coord_system2), 1)
c2.add_dim_coord(
iris.coords.DimCoord(np.arange(1, 3),
'longitude',
long_name='2',
units='degrees',
coord_system=coord_system2), 0)
c3.add_dim_coord(
iris.coords.DimCoord(np.arange(1, 3),
'grid_latitude',
long_name='3',
units='degrees',
coord_system=coord_system3), 1)
c3.add_dim_coord(
iris.coords.DimCoord(np.arange(1, 3),
'grid_longitude',
long_name='3',
units='degrees',
coord_system=coord_system3), 0)
cubes = iris.cube.CubeList([c1, c2, c3])
with self.temp_filename(suffix='.nc') as file_out:
iris.save(cubes, file_out)
# Check the netCDF file against CDL expected output.
self.assertCDL(file_out,
('netcdf', 'netcdf_save_gridmapmulti.cdl'))
def test_lat_lon_major_minor(self):
major = 63781370
minor = 63567523
self.grid.semi_major_axis = major
self.grid.semi_minor_axis = minor
crs = pyke_rules.build_coordinate_system(self.grid)
self.assertEqual(crs, icoord_systems.GeogCS(major, minor))
def _cube_data(data):
"""Returns a cube given a list of lat lon information."""
cube = iris.cube.Cube(data)
lat_lon_coord_system = icoord_systems.GeogCS(6371229)
step = 4.0
start = step / 2
count = 90
pts = start + numpy.arange(count, dtype=numpy.float32) * step
lon_coord = icoords.DimCoord(pts,
standard_name='longitude',
units='degrees',
coord_system=lat_lon_coord_system,
circular=True)
lon_coord.guess_bounds()
start = -90
step = 4.0
count = 45
pts = start + numpy.arange(count, dtype=numpy.float32) * step
lat_coord = icoords.DimCoord(pts,
standard_name='latitude',
units='degrees',
coord_system=lat_lon_coord_system)
lat_coord.guess_bounds()
cube.add_dim_coord(lat_coord, 0)
cube.add_dim_coord(lon_coord, 1)
return cube
def test_load_tmerc_grid_with_projection_origin(self):
# Test loading a single CF-netCDF file with a transverse Mercator
# grid_mapping that uses longitude_of_projection_origin and
# scale_factor_at_projection_origin instead of
# longitude_of_central_meridian and scale_factor_at_central_meridian.
cube = iris.load_cube(
tests.get_data_path((
"NetCDF",
"transverse_mercator",
"projection_origin_attributes.nc",
)))
expected = icoord_systems.TransverseMercator(
latitude_of_projection_origin=49.0,
longitude_of_central_meridian=-2.0,
false_easting=400000.0,
false_northing=-100000.0,
scale_factor_at_central_meridian=0.9996012717,
ellipsoid=icoord_systems.GeogCS(semi_major_axis=6377563.396,
semi_minor_axis=6356256.91),
)
self.assertEqual(
cube.coord("projection_x_coordinate").coord_system, expected)
self.assertEqual(
cube.coord("projection_y_coordinate").coord_system, expected)
def NAME_to_cube(filenames, callback):
"""Returns a generator of cubes given a list of filenames and a callback."""
for filename in filenames:
header, column_headings, data_arrays = load_NAME_III(filename)
for i, data_array in enumerate(data_arrays):
# turn the dictionary of column headers with a list of header information for each field into a dictionary of
# headers for just this field. Ignore the first 4 columns of grid position (data was located with the data array).
field_headings = dict([(k, v[i + 4]) for k, v in column_headings.iteritems()])
# make an cube
cube = iris.cube.Cube(data_array)
# define the name and unit
name = ('%s %s' % (field_headings['species'], field_headings['quantity'])).upper().replace(' ', '_')
cube.rename(name)
# Some units are badly encoded in the file, fix this by putting a space in between. (if gs is not found, then the
# string will be returned unchanged)
cube.units = field_headings['unit'].replace('gs', 'g s')
# define and add the singular coordinates of the field (flight level, time etc.)
cube.add_aux_coord(icoords.AuxCoord(field_headings['z_level'], long_name='flight_level', units='1'))
# define the time unit and use it to serialise the datetime for the time coordinate
time_unit = iris.unit.Unit('hours since epoch', calendar=iris.unit.CALENDAR_GREGORIAN)
time_coord = icoords.AuxCoord(time_unit.date2num(field_headings['time']), standard_name='time', units=time_unit)
cube.add_aux_coord(time_coord)
# build a coordinate system which can be referenced by latitude and longitude coordinates
lat_lon_coord_system = icoord_systems.GeogCS(6371229)
# build regular latitude and longitude coordinates which have bounds
start = header['X grid origin'] + header['X grid resolution']
step = header['X grid resolution']
count = header['X grid size']
pts = start + np.arange(count, dtype=np.float32) * step
lon_coord = icoords.DimCoord(pts, standard_name='longitude', units='degrees', coord_system=lat_lon_coord_system)
lon_coord.guess_bounds()
start = header['Y grid origin'] + header['Y grid resolution']
step = header['Y grid resolution']
count = header['Y grid size']
pts = start + np.arange(count, dtype=np.float32) * step
lat_coord = icoords.DimCoord(pts, standard_name='latitude', units='degrees', coord_system=lat_lon_coord_system)
lat_coord.guess_bounds()
# add the latitude and longitude coordinates to the cube, with mappings to data dimensions
cube.add_dim_coord(lat_coord, 0)
cube.add_dim_coord(lon_coord, 1)
# implement standard iris callback capability. Although callbacks are not used in this example, the standard
# mechanism for a custom loader to implement a callback is shown:
cube = iris.io.run_callback(callback, cube, [header, field_headings, data_array], filename)
# yield the cube created (the loop will continue when the next() element is requested)
yield cube
def test_oblate_shape_3_7(self):
for shape in [3, 7]:
major, minor = 1, 10
scale = 1
result = ellipsoid(shape, major, minor, MDI)
if shape == 3:
# Convert km to m.
scale = 1000
expected = icoord_systems.GeogCS(major * scale, minor * scale)
self.assertEqual(result, expected)
def _compute_extra_keys(self):
"""Compute our extra keys."""
global unknown_string
self.extra_keys = {}
forecastTime = self.startStep
# regular or rotated grid?
try:
longitudeOfSouthernPoleInDegrees = \
self.longitudeOfSouthernPoleInDegrees
latitudeOfSouthernPoleInDegrees = \
self.latitudeOfSouthernPoleInDegrees
except AttributeError:
longitudeOfSouthernPoleInDegrees = 0.0
latitudeOfSouthernPoleInDegrees = 90.0
centre = gribapi.grib_get_string(self.grib_message, "centre")
# default values
self.extra_keys = {
'_referenceDateTime': -1.0,
'_phenomenonDateTime': -1.0,
'_periodStartDateTime': -1.0,
'_periodEndDateTime': -1.0,
'_levelTypeName': unknown_string,
'_levelTypeUnits': unknown_string,
'_firstLevelTypeName': unknown_string,
'_firstLevelTypeUnits': unknown_string,
'_firstLevel': -1.0,
'_secondLevelTypeName': unknown_string,
'_secondLevel': -1.0,
'_originatingCentre': unknown_string,
'_forecastTime': None,
'_forecastTimeUnit': unknown_string,
'_coord_system': None,
'_x_circular': False,
'_x_coord_name': unknown_string,
'_y_coord_name': unknown_string,
# These are here to avoid repetition in the rules
# files, and reduce the very long line lengths.
'_x_points': None,
'_y_points': None,
'_cf_data': None
}
# cf phenomenon translation
# Get centre code (N.B. self.centre has default type = string)
centre_number = gribapi.grib_get_long(self.grib_message, "centre")
# Look for a known grib1-to-cf translation (or None).
cf_data = gptx.grib1_phenom_to_cf_info(
table2_version=self.table2Version,
centre_number=centre_number,
param_number=self.indicatorOfParameter)
self.extra_keys['_cf_data'] = cf_data
# reference date
self.extra_keys['_referenceDateTime'] = \
datetime.datetime(int(self.year), int(self.month), int(self.day),
int(self.hour), int(self.minute))
# forecast time with workarounds
self.extra_keys['_forecastTime'] = forecastTime
# verification date
processingDone = self._get_processing_done()
# time processed?
if processingDone.startswith("time"):
validityDate = str(self.validityDate)
validityTime = "{:04}".format(int(self.validityTime))
endYear = int(validityDate[:4])
endMonth = int(validityDate[4:6])
endDay = int(validityDate[6:8])
endHour = int(validityTime[:2])
endMinute = int(validityTime[2:4])
# fixed forecastTime in hours
self.extra_keys['_periodStartDateTime'] = \
(self.extra_keys['_referenceDateTime'] +
datetime.timedelta(hours=int(forecastTime)))
self.extra_keys['_periodEndDateTime'] = \
datetime.datetime(endYear, endMonth, endDay, endHour,
endMinute)
else:
self.extra_keys['_phenomenonDateTime'] = \
self._get_verification_date()
# originating centre
# TODO #574 Expand to include sub-centre
self.extra_keys['_originatingCentre'] = CENTRE_TITLES.get(
centre, "unknown centre %s" % centre)
# forecast time unit as a cm string
# TODO #575 Do we want PP or GRIB style forecast delta?
self.extra_keys['_forecastTimeUnit'] = self._timeunit_string()
# shape of the earth
# pre-defined sphere
if self.shapeOfTheEarth == 0:
geoid = coord_systems.GeogCS(semi_major_axis=6367470)
# custom sphere
elif self.shapeOfTheEarth == 1:
geoid = coord_systems.GeogCS(
self.scaledValueOfRadiusOfSphericalEarth *
10**-self.scaleFactorOfRadiusOfSphericalEarth)
# IAU65 oblate sphere
elif self.shapeOfTheEarth == 2:
geoid = coord_systems.GeogCS(6378160, inverse_flattening=297.0)
# custom oblate spheroid (km)
elif self.shapeOfTheEarth == 3:
geoid = coord_systems.GeogCS(
semi_major_axis=self.scaledValueOfEarthMajorAxis *
10**-self.scaleFactorOfEarthMajorAxis * 1000.,
semi_minor_axis=self.scaledValueOfEarthMinorAxis *
10**-self.scaleFactorOfEarthMinorAxis * 1000.)
# IAG-GRS80 oblate spheroid
elif self.shapeOfTheEarth == 4:
geoid = coord_systems.GeogCS(6378137, None, 298.257222101)
# WGS84
elif self.shapeOfTheEarth == 5:
geoid = \
coord_systems.GeogCS(6378137, inverse_flattening=298.257223563)
# pre-defined sphere
elif self.shapeOfTheEarth == 6:
geoid = coord_systems.GeogCS(6371229)
# custom oblate spheroid (m)
elif self.shapeOfTheEarth == 7:
geoid = coord_systems.GeogCS(
semi_major_axis=self.scaledValueOfEarthMajorAxis *
10**-self.scaleFactorOfEarthMajorAxis,
semi_minor_axis=self.scaledValueOfEarthMinorAxis *
10**-self.scaleFactorOfEarthMinorAxis)
elif self.shapeOfTheEarth == 8:
raise ValueError("unhandled shape of earth : grib earth shape = 8")
else:
raise ValueError("undefined shape of earth")
gridType = gribapi.grib_get_string(self.grib_message, "gridType")
if gridType in [
"regular_ll", "regular_gg", "reduced_ll", "reduced_gg"
]:
self.extra_keys['_x_coord_name'] = "longitude"
self.extra_keys['_y_coord_name'] = "latitude"
self.extra_keys['_coord_system'] = geoid
elif gridType == 'rotated_ll':
# TODO: Confirm the translation from angleOfRotation to
# north_pole_lon (usually 0 for both)
self.extra_keys['_x_coord_name'] = "grid_longitude"
self.extra_keys['_y_coord_name'] = "grid_latitude"
southPoleLon = longitudeOfSouthernPoleInDegrees
southPoleLat = latitudeOfSouthernPoleInDegrees
self.extra_keys['_coord_system'] = \
coord_systems.RotatedGeogCS(
-southPoleLat,
math.fmod(southPoleLon + 180.0, 360.0),
self.angleOfRotation, geoid)
elif gridType == 'polar_stereographic':
self.extra_keys['_x_coord_name'] = "projection_x_coordinate"
self.extra_keys['_y_coord_name'] = "projection_y_coordinate"
if self.projectionCentreFlag == 0:
pole_lat = 90
elif self.projectionCentreFlag == 1:
pole_lat = -90
else:
raise TranslationError("Unhandled projectionCentreFlag")
# Note: I think the grib api defaults LaDInDegrees to 60 for grib1.
self.extra_keys['_coord_system'] = \
coord_systems.Stereographic(
pole_lat, self.orientationOfTheGridInDegrees, 0, 0,
self.LaDInDegrees, ellipsoid=geoid)
elif gridType == 'lambert':
self.extra_keys['_x_coord_name'] = "projection_x_coordinate"
self.extra_keys['_y_coord_name'] = "projection_y_coordinate"
flag_name = "projectionCenterFlag"
if getattr(self, flag_name) == 0:
pole_lat = 90
elif getattr(self, flag_name) == 1:
pole_lat = -90
else:
raise TranslationError("Unhandled projectionCentreFlag")
LambertConformal = coord_systems.LambertConformal
self.extra_keys['_coord_system'] = LambertConformal(
self.LaDInDegrees,
self.LoVInDegrees,
0,
0,
secant_latitudes=(self.Latin1InDegrees, self.Latin2InDegrees),
ellipsoid=geoid)
else:
raise TranslationError("unhandled grid type: {}".format(gridType))
if gridType in ["regular_ll", "rotated_ll"]:
self._regular_longitude_common()
j_step = self.jDirectionIncrementInDegrees
if not self.jScansPositively:
j_step = -j_step
self._y_points = (np.arange(self.Nj, dtype=np.float64) * j_step +
self.latitudeOfFirstGridPointInDegrees)
elif gridType in ['regular_gg']:
# longitude coordinate is straight-forward
self._regular_longitude_common()
# get the distinct latitudes, and make sure they are sorted
# (south-to-north) and then put them in the right direction
# depending on the scan direction
latitude_points = gribapi.grib_get_double_array(
self.grib_message, 'distinctLatitudes').astype(np.float64)
latitude_points.sort()
if not self.jScansPositively:
# we require latitudes north-to-south
self._y_points = latitude_points[::-1]
else:
self._y_points = latitude_points
elif gridType in ["polar_stereographic", "lambert"]:
# convert the starting latlon into meters
cartopy_crs = self.extra_keys['_coord_system'].as_cartopy_crs()
x1, y1 = cartopy_crs.transform_point(
self.longitudeOfFirstGridPointInDegrees,
self.latitudeOfFirstGridPointInDegrees, ccrs.Geodetic())
if not np.all(np.isfinite([x1, y1])):
raise TranslationError("Could not determine the first latitude"
" and/or longitude grid point.")
self._x_points = x1 + self.DxInMetres * np.arange(self.Nx,
dtype=np.float64)
self._y_points = y1 + self.DyInMetres * np.arange(self.Ny,
dtype=np.float64)
elif gridType in ["reduced_ll", "reduced_gg"]:
self._x_points = self.longitudes
self._y_points = self.latitudes
else:
raise TranslationError("unhandled grid type")
def test_lat_lon_earth_radius(self):
earth_radius = 63700000
self.grid.earth_radius = earth_radius
crs = pyke_rules.build_coordinate_system(self.grid)
self.assertEqual(crs, icoord_systems.GeogCS(earth_radius))
def NAME_to_cube(filenames, callback):
"""
Returns a generator of cubes given a list of filenames and a callback.
"""
for filename in filenames:
header, column_headings, data_arrays = load_NAME_III(filename)
for i, data_array in enumerate(data_arrays):
# turn the dictionary of column headers with a list of header
# information for each field into a dictionary of headers for just
# this field. Ignore the first 4 columns of grid position (data was
# located with the data array).
field_headings = dict(
(k, v[i + 4]) for k, v in column_headings.items())
# make an cube
cube = iris.cube.Cube(data_array)
# define the name and unit
name = "%s %s" % (
field_headings["species"],
field_headings["quantity"],
)
name = name.upper().replace(" ", "_")
cube.rename(name)
# Some units are badly encoded in the file, fix this by putting a
# space in between. (if gs is not found, then the string will be
# returned unchanged)
cube.units = field_headings["unit"].replace("gs", "g s")
# define and add the singular coordinates of the field (flight
# level, time etc.)
cube.add_aux_coord(
icoords.AuxCoord(
field_headings["z_level"],
long_name="flight_level",
units="1",
))
# define the time unit and use it to serialise the datetime for the
# time coordinate
time_unit = Unit("hours since epoch", calendar=CALENDAR_GREGORIAN)
time_coord = icoords.AuxCoord(
time_unit.date2num(field_headings["time"]),
standard_name="time",
units=time_unit,
)
cube.add_aux_coord(time_coord)
# build a coordinate system which can be referenced by latitude and
# longitude coordinates
lat_lon_coord_system = icoord_systems.GeogCS(6371229)
# build regular latitude and longitude coordinates which have
# bounds
start = header["X grid origin"] + header["X grid resolution"]
step = header["X grid resolution"]
count = header["X grid size"]
pts = start + np.arange(count, dtype=np.float32) * step
lon_coord = icoords.DimCoord(
pts,
standard_name="longitude",
units="degrees",
coord_system=lat_lon_coord_system,
)
lon_coord.guess_bounds()
start = header["Y grid origin"] + header["Y grid resolution"]
step = header["Y grid resolution"]
count = header["Y grid size"]
pts = start + np.arange(count, dtype=np.float32) * step
lat_coord = icoords.DimCoord(
pts,
standard_name="latitude",
units="degrees",
coord_system=lat_lon_coord_system,
)
lat_coord.guess_bounds()
# add the latitude and longitude coordinates to the cube, with
# mappings to data dimensions
cube.add_dim_coord(lat_coord, 0)
cube.add_dim_coord(lon_coord, 1)
# implement standard iris callback capability. Although callbacks
# are not used in this example, the standard mechanism for a custom
# loader to implement a callback is shown:
cube = iris.io.run_callback(callback, cube,
[header, field_headings, data_array],
filename)
# yield the cube created (the loop will continue when the next()
# element is requested)
yield cube
def setUp(self):
plt.figure()
self.geog_cs = ics.GeogCS(6371229.0)
self.plate_carree = self.geog_cs.as_cartopy_projection()
def test_netcdf_save_gridmapping(self):
# Test saving CF-netCDF from a cubelist with various grid mappings.
c1 = self.cubell
c2 = self.cubell.copy()
c3 = self.cubell.copy()
coord_system = icoord_systems.GeogCS(6371229)
coord_system2 = icoord_systems.GeogCS(6371228)
coord_system3 = icoord_systems.RotatedGeogCS(30, 30)
c1.add_dim_coord(
iris.coords.DimCoord(
np.arange(1, 3),
"latitude",
long_name="1",
units="degrees",
coord_system=coord_system,
),
1,
)
c1.add_dim_coord(
iris.coords.DimCoord(
np.arange(1, 3),
"longitude",
long_name="1",
units="degrees",
coord_system=coord_system,
),
0,
)
c2.add_dim_coord(
iris.coords.DimCoord(
np.arange(1, 3),
"latitude",
long_name="2",
units="degrees",
coord_system=coord_system2,
),
1,
)
c2.add_dim_coord(
iris.coords.DimCoord(
np.arange(1, 3),
"longitude",
long_name="2",
units="degrees",
coord_system=coord_system2,
),
0,
)
c3.add_dim_coord(
iris.coords.DimCoord(
np.arange(1, 3),
"grid_latitude",
long_name="3",
units="degrees",
coord_system=coord_system3,
),
1,
)
c3.add_dim_coord(
iris.coords.DimCoord(
np.arange(1, 3),
"grid_longitude",
long_name="3",
units="degrees",
coord_system=coord_system3,
),
0,
)
cubes = iris.cube.CubeList([c1, c2, c3])
with self.temp_filename(suffix=".nc") as file_out:
iris.save(cubes, file_out)
# Check the netCDF file against CDL expected output.
self.assertCDL(file_out,
("netcdf", "netcdf_save_gridmapmulti.cdl"))
def test_spherical_shape_1(self):
shape = 1
radius = 10
result = ellipsoid(shape, MDI, MDI, radius)
expected = icoord_systems.GeogCS(radius)
self.assertEqual(result, expected)
if short_name == "2t":
color_plot_dist = values_range_for_plot / 20
bounds = np.arange(total_min, total_max + color_plot_dist,
color_plot_dist)
color_bar_dist = values_range_for_plot / 10
cmap = plt.get_cmap(colormap)
time_after_init = start_time_since_init + i * plot_interval
if surface_bool == 0:
print("plotting " + short_name + " at level " + str(level) +
" for t - t_init = " + str(time_after_init) + " s ...")
if surface_bool == 1:
print("plotting " + short_name + " for t - t_init = " +
str(time_after_init) + " s ...")
if (projection == "Orthographic"):
fig = plt.figure(figsize=(fig_size, fig_size))
coord_sys = cs.GeogCS(6371229)
if (projection == "Mollweide"):
fig = plt.figure(figsize=(fig_size, 0.5 * fig_size))
coord_sys = cs.GeogCS(6371229)
if (projection == "EckertIII"):
fig = plt.figure(figsize=(fig_size, 0.5 * fig_size))
coord_sys = cs.GeogCS(6371229)
if (projection == "Orthographic"):
fig = plt.figure(figsize=(fig_size, fig_size))
ax = plt.axes(projection=ccrs.Orthographic(central_latitude=0,
central_longitude=0))
coord_sys = cs.GeogCS(6371229)
if (projection == "Mollweide"):
fig = plt.figure(figsize=(fig_size, fig_size))
ax = plt.axes(projection=ccrs.Mollweide())
coord_sys = cs.GeogCS(6371229)
def _compute_extra_keys(self):
"""Compute our extra keys."""
global unknown_string
self.extra_keys = {}
# work out stuff based on these values from the message
edition = self.edition
# time-processed forcast time is from reference time to start of period
if edition == 2:
forecastTime = self.forecastTime
uft = np.uint32(forecastTime)
BILL = 2**30
# Workaround grib api's assumption that forecast time is positive.
# Handles correctly encoded -ve forecast times up to one -1 billion.
if hindcast_workaround:
if 2 * BILL < uft < 3 * BILL:
msg = "Re-interpreting negative forecastTime from " \
+ str(forecastTime)
forecastTime = -(uft - 2 * BILL)
msg += " to " + str(forecastTime)
warnings.warn(msg)
else:
forecastTime = self.startStep
#regular or rotated grid?
try:
longitudeOfSouthernPoleInDegrees = self.longitudeOfSouthernPoleInDegrees
latitudeOfSouthernPoleInDegrees = self.latitudeOfSouthernPoleInDegrees
except AttributeError:
longitudeOfSouthernPoleInDegrees = 0.0
latitudeOfSouthernPoleInDegrees = 90.0
centre = gribapi.grib_get_string(self.grib_message, "centre")
#default values
self.extra_keys = {
'_referenceDateTime': -1.0,
'_phenomenonDateTime': -1.0,
'_periodStartDateTime': -1.0,
'_periodEndDateTime': -1.0,
'_levelTypeName': unknown_string,
'_levelTypeUnits': unknown_string,
'_firstLevelTypeName': unknown_string,
'_firstLevelTypeUnits': unknown_string,
'_firstLevel': -1.0,
'_secondLevelTypeName': unknown_string,
'_secondLevel': -1.0,
'_originatingCentre': unknown_string,
'_forecastTime': None,
'_forecastTimeUnit': unknown_string,
'_coord_system': None,
'_x_circular': False,
'_x_coord_name': unknown_string,
'_y_coord_name': unknown_string,
# These are here to avoid repetition in the rules files,
# and reduce the very long line lengths.
'_x_points': None,
'_y_points': None,
'_cf_data': None
}
# cf phenomenon translation
if edition == 1:
# Get centre code (N.B. self.centre has default type = string)
centre_number = gribapi.grib_get_long(self.grib_message, "centre")
# Look for a known grib1-to-cf translation (or None).
cf_data = gptx.grib1_phenom_to_cf_info(
table2_version=self.table2Version,
centre_number=centre_number,
param_number=self.indicatorOfParameter)
self.extra_keys['_cf_data'] = cf_data
elif edition == 2:
# Don't attempt to interpret params if 'master tables version' is
# 255, as local params may then have same codes as standard ones.
if self.tablesVersion != 255:
# Look for a known grib2-to-cf translation (or None).
cf_data = gptx.grib2_phenom_to_cf_info(
param_discipline=self.discipline,
param_category=self.parameterCategory,
param_number=self.parameterNumber)
self.extra_keys['_cf_data'] = cf_data
#reference date
self.extra_keys['_referenceDateTime'] = \
datetime.datetime(int(self.year), int(self.month), int(self.day),
int(self.hour), int(self.minute))
# forecast time with workarounds
self.extra_keys['_forecastTime'] = forecastTime
#verification date
processingDone = self._get_processing_done()
#time processed?
if processingDone.startswith("time"):
if self.edition == 1:
validityDate = str(self.validityDate)
validityTime = "{:04}".format(int(self.validityTime))
endYear = int(validityDate[:4])
endMonth = int(validityDate[4:6])
endDay = int(validityDate[6:8])
endHour = int(validityTime[:2])
endMinute = int(validityTime[2:4])
elif self.edition == 2:
endYear = self.yearOfEndOfOverallTimeInterval
endMonth = self.monthOfEndOfOverallTimeInterval
endDay = self.dayOfEndOfOverallTimeInterval
endHour = self.hourOfEndOfOverallTimeInterval
endMinute = self.minuteOfEndOfOverallTimeInterval
# fixed forecastTime in hours
self.extra_keys['_periodStartDateTime'] = \
(self.extra_keys['_referenceDateTime'] +
datetime.timedelta(hours=int(forecastTime)))
self.extra_keys['_periodEndDateTime'] = \
datetime.datetime(endYear, endMonth, endDay, endHour, endMinute)
else:
self.extra_keys[
'_phenomenonDateTime'] = self._get_verification_date()
#originating centre
#TODO #574 Expand to include sub-centre
self.extra_keys['_originatingCentre'] = CENTRE_TITLES.get(
centre, "unknown centre %s" % centre)
#forecast time unit as a cm string
#TODO #575 Do we want PP or GRIB style forecast delta?
self.extra_keys['_forecastTimeUnit'] = self._timeunit_string()
#shape of the earth
#pre-defined sphere
if self.shapeOfTheEarth == 0:
geoid = coord_systems.GeogCS(semi_major_axis=6367470)
#custom sphere
elif self.shapeOfTheEarth == 1:
geoid = \
coord_systems.GeogCS(self.scaledValueOfRadiusOfSphericalEarth * \
self.scaleFactorOfRadiusOfSphericalEarth)
#IAU65 oblate sphere
elif self.shapeOfTheEarth == 2:
geoid = coord_systems.GeogCS(6378160, inverse_flattening=297.0)
#custom oblate spheroid (km)
elif self.shapeOfTheEarth == 3:
geoid = coord_systems.GeogCS(
semi_major_axis=self.scaledValueOfEarthMajorAxis *
self.scaleFactorOfEarthMajorAxis * 1000.0,
semi_minor_axis=self.scaledValueOfEarthMinorAxis *
self.scaleFactorOfEarthMinorAxis * 1000.0)
#IAG-GRS80 oblate spheroid
elif self.shapeOfTheEarth == 4:
geoid = coord_systems.GeogCS(6378137, None, 298.257222101)
#WGS84
elif self.shapeOfTheEarth == 5:
geoid = \
coord_systems.GeogCS(6378137, inverse_flattening=298.257223563)
#pre-defined sphere
elif self.shapeOfTheEarth == 6:
geoid = coord_systems.GeogCS(6371229)
#custom oblate spheroid (m)
elif self.shapeOfTheEarth == 7:
geoid = coord_systems.GeogCS(
semi_major_axis=self.scaledValueOfEarthMajorAxis *
self.scaleFactorOfEarthMajorAxis,
semi_minor_axis=self.scaledValueOfEarthMinorAxis *
self.scaleFactorOfEarthMinorAxis)
elif self.shapeOfTheEarth == 8:
raise ValueError("unhandled shape of earth : grib earth shape = 8")
else:
raise ValueError("undefined shape of earth")
gridType = gribapi.grib_get_string(self.grib_message, "gridType")
if gridType == "regular_ll":
self.extra_keys['_x_coord_name'] = "longitude"
self.extra_keys['_y_coord_name'] = "latitude"
self.extra_keys['_coord_system'] = geoid
elif gridType == 'rotated_ll':
# TODO: Confirm the translation from angleOfRotation to
# north_pole_lon (usually 0 for both)
self.extra_keys['_x_coord_name'] = "grid_longitude"
self.extra_keys['_y_coord_name'] = "grid_latitude"
southPoleLon = longitudeOfSouthernPoleInDegrees
southPoleLat = latitudeOfSouthernPoleInDegrees
self.extra_keys['_coord_system'] = \
iris.coord_systems.RotatedGeogCS(
-southPoleLat,
math.fmod(southPoleLon + 180.0, 360.0),
self.angleOfRotation, geoid)
elif gridType == 'polar_stereographic':
self.extra_keys['_x_coord_name'] = "projection_x_coordinate"
self.extra_keys['_y_coord_name'] = "projection_y_coordinate"
if self.projectionCentreFlag == 0:
pole_lat = 90
elif self.projectionCentreFlag == 1:
pole_lat = -90
else:
raise TranslationError("Unhandled projectionCentreFlag")
# Note: I think the grib api defaults LaDInDegrees to 60 for grib1.
self.extra_keys['_coord_system'] = \
iris.coord_systems.Stereographic(
pole_lat, self.orientationOfTheGridInDegrees, 0, 0,
self.LaDInDegrees, ellipsoid=geoid)
else:
raise TranslationError("unhandled grid type")
# x and y points, and circularity
if gridType in ["regular_ll", "rotated_ll"]:
i_step = self.iDirectionIncrementInDegrees
j_step = self.jDirectionIncrementInDegrees
if self.iScansNegatively:
i_step = -i_step
if not self.jScansPositively:
j_step = -j_step
self._x_points = (np.arange(self.Ni, dtype=np.float64) * i_step +
self.longitudeOfFirstGridPointInDegrees)
self._y_points = (np.arange(self.Nj, dtype=np.float64) * j_step +
self.latitudeOfFirstGridPointInDegrees)
# circular x coord?
if "longitude" in self.extra_keys['_x_coord_name'] and self.Ni > 1:
# Is the gap from end to start smaller,
# or about equal to the max step?
points = self._x_points
gap = 360.0 - abs(points[-1] - points[0])
max_step = abs(np.diff(points)).max()
if gap <= max_step:
self.extra_keys['_x_circular'] = True
else:
delta = 0.001
if abs(1.0 - gap / max_step) < delta:
self.extra_keys['_x_circular'] = True
elif gridType == "polar_stereographic":
# convert the starting latlon into meters
cartopy_crs = self.extra_keys['_coord_system'].as_cartopy_crs()
x1, y1 = cartopy_crs.transform_point(
self.longitudeOfFirstGridPointInDegrees,
self.latitudeOfFirstGridPointInDegrees, cartopy.crs.Geodetic())
self._x_points = x1 + self.DxInMetres * np.arange(self.Nx,
dtype=np.float64)
self._y_points = y1 + self.DyInMetres * np.arange(self.Ny,
dtype=np.float64)
else:
raise TranslationError("unhandled grid type")
def _compute_extra_keys(self):
"""Compute our extra keys."""
global unknown_string
self.extra_keys = {}
forecastTime = self.startStep
# regular or rotated grid?
try:
longitudeOfSouthernPoleInDegrees = \
self.longitudeOfSouthernPoleInDegrees
latitudeOfSouthernPoleInDegrees = \
self.latitudeOfSouthernPoleInDegrees
except AttributeError:
longitudeOfSouthernPoleInDegrees = 0.0
latitudeOfSouthernPoleInDegrees = 90.0
centre = gribapi.grib_get_string(self.grib_message, "centre")
# default values
self.extra_keys = {'_referenceDateTime': -1.0,
'_phenomenonDateTime': -1.0,
'_periodStartDateTime': -1.0,
'_periodEndDateTime': -1.0,
'_levelTypeName': unknown_string,
'_levelTypeUnits': unknown_string,
'_firstLevelTypeName': unknown_string,
'_firstLevelTypeUnits': unknown_string,
'_firstLevel': -1.0,
'_secondLevelTypeName': unknown_string,
'_secondLevel': -1.0,
'_originatingCentre': unknown_string,
'_forecastTime': None,
'_forecastTimeUnit': unknown_string,
'_coord_system': None,
'_x_circular': False,
'_x_coord_name': unknown_string,
'_y_coord_name': unknown_string,
# These are here to avoid repetition in the rules
# files, and reduce the very long line lengths.
'_x_points': None,
'_y_points': None,
'_cf_data': None}
# cf phenomenon translation
# Get centre code (N.B. self.centre has default type = string)
centre_number = gribapi.grib_get_long(self.grib_message, "centre")
# Look for a known grib1-to-cf translation (or None).
cf_data = gptx.grib1_phenom_to_cf_info(
table2_version=self.table2Version,
centre_number=centre_number,
param_number=self.indicatorOfParameter)
self.extra_keys['_cf_data'] = cf_data
# reference date
self.extra_keys['_referenceDateTime'] = \
datetime.datetime(int(self.year), int(self.month), int(self.day),
int(self.hour), int(self.minute))
# forecast time with workarounds
self.extra_keys['_forecastTime'] = forecastTime
# verification date
processingDone = self._get_processing_done()
# time processed?
if processingDone.startswith("time"):
validityDate = str(self.validityDate)
validityTime = "{:04}".format(int(self.validityTime))
endYear = int(validityDate[:4])
endMonth = int(validityDate[4:6])
endDay = int(validityDate[6:8])
endHour = int(validityTime[:2])
endMinute = int(validityTime[2:4])
# fixed forecastTime in hours
self.extra_keys['_periodStartDateTime'] = \
(self.extra_keys['_referenceDateTime'] +
datetime.timedelta(hours=int(forecastTime)))
self.extra_keys['_periodEndDateTime'] = \
datetime.datetime(endYear, endMonth, endDay, endHour,
endMinute)
else:
self.extra_keys['_phenomenonDateTime'] = \
self._get_verification_date()
# originating centre
# TODO #574 Expand to include sub-centre
self.extra_keys['_originatingCentre'] = CENTRE_TITLES.get(
centre, "unknown centre %s" % centre)
# forecast time unit as a cm string
# TODO #575 Do we want PP or GRIB style forecast delta?
self.extra_keys['_forecastTimeUnit'] = self._timeunit_string()
# shape of the earth
soe_code = self.shapeOfTheEarth
# As this class is now *only* for GRIB1, 'shapeOfTheEarth' is not a
# value read from the actual file : It is really a GRIB2 param, and
# the value is merely what eccodes (gribapi) gives as the default.
# This was always = 6, until eccodes 0.19, when it changed to 0.
# See https://jira.ecmwf.int/browse/ECC-811
# The two represent different sized spherical earths.
if soe_code not in (6, 0):
raise ValueError('Unexpected shapeOfTheEarth value =', soe_code)
soe_code = 6
# *FOR NOW* maintain the old behaviour (radius=6371229) in all cases,
# for backwards compatibility.
# However, this does not match the 'radiusOfTheEarth' default from the
# gribapi so is probably incorrect (see above issue ECC-811).
# So we may change this in future.
if soe_code == 0:
# New supposedly-correct default value, matches 'radiusOfTheEarth'.
geoid = coord_systems.GeogCS(semi_major_axis=6367470)
elif soe_code == 6:
# Old value, does *not* match the 'radiusOfTheEarth' parameter.
geoid = coord_systems.GeogCS(6371229)
gridType = gribapi.grib_get_string(self.grib_message, "gridType")
if gridType in ["regular_ll", "regular_gg", "reduced_ll",
"reduced_gg"]:
self.extra_keys['_x_coord_name'] = "longitude"
self.extra_keys['_y_coord_name'] = "latitude"
self.extra_keys['_coord_system'] = geoid
elif gridType == 'rotated_ll':
# TODO: Confirm the translation from angleOfRotation to
# north_pole_lon (usually 0 for both)
self.extra_keys['_x_coord_name'] = "grid_longitude"
self.extra_keys['_y_coord_name'] = "grid_latitude"
southPoleLon = longitudeOfSouthernPoleInDegrees
southPoleLat = latitudeOfSouthernPoleInDegrees
self.extra_keys['_coord_system'] = \
coord_systems.RotatedGeogCS(
-southPoleLat,
math.fmod(southPoleLon + 180.0, 360.0),
self.angleOfRotation, geoid)
elif gridType == 'polar_stereographic':
self.extra_keys['_x_coord_name'] = "projection_x_coordinate"
self.extra_keys['_y_coord_name'] = "projection_y_coordinate"
if self.projectionCentreFlag == 0:
pole_lat = 90
elif self.projectionCentreFlag == 1:
pole_lat = -90
else:
raise TranslationError("Unhandled projectionCentreFlag")
# Note: I think the grib api defaults LaDInDegrees to 60 for grib1.
self.extra_keys['_coord_system'] = \
coord_systems.Stereographic(
pole_lat, self.orientationOfTheGridInDegrees, 0, 0,
self.LaDInDegrees, ellipsoid=geoid)
elif gridType == 'lambert':
self.extra_keys['_x_coord_name'] = "projection_x_coordinate"
self.extra_keys['_y_coord_name'] = "projection_y_coordinate"
flag_name = "projectionCenterFlag"
if getattr(self, flag_name) == 0:
pole_lat = 90
elif getattr(self, flag_name) == 1:
pole_lat = -90
else:
raise TranslationError("Unhandled projectionCentreFlag")
LambertConformal = coord_systems.LambertConformal
self.extra_keys['_coord_system'] = LambertConformal(
self.LaDInDegrees, self.LoVInDegrees, 0, 0,
secant_latitudes=(self.Latin1InDegrees, self.Latin2InDegrees),
ellipsoid=geoid)
else:
raise TranslationError("unhandled grid type: {}".format(gridType))
if gridType in ["regular_ll", "rotated_ll"]:
self._regular_longitude_common()
j_step = self.jDirectionIncrementInDegrees
if not self.jScansPositively:
j_step = -j_step
self._y_points = (np.arange(self.Nj, dtype=np.float64) * j_step +
self.latitudeOfFirstGridPointInDegrees)
elif gridType in ['regular_gg']:
# longitude coordinate is straight-forward
self._regular_longitude_common()
# get the distinct latitudes, and make sure they are sorted
# (south-to-north) and then put them in the right direction
# depending on the scan direction
latitude_points = gribapi.grib_get_double_array(
self.grib_message, 'distinctLatitudes').astype(np.float64)
latitude_points.sort()
if not self.jScansPositively:
# we require latitudes north-to-south
self._y_points = latitude_points[::-1]
else:
self._y_points = latitude_points
elif gridType in ["polar_stereographic", "lambert"]:
# convert the starting latlon into meters
cartopy_crs = self.extra_keys['_coord_system'].as_cartopy_crs()
x1, y1 = cartopy_crs.transform_point(
self.longitudeOfFirstGridPointInDegrees,
self.latitudeOfFirstGridPointInDegrees,
ccrs.Geodetic())
if not np.all(np.isfinite([x1, y1])):
raise TranslationError("Could not determine the first latitude"
" and/or longitude grid point.")
self._x_points = x1 + self.DxInMetres * np.arange(self.Nx,
dtype=np.float64)
self._y_points = y1 + self.DyInMetres * np.arange(self.Ny,
dtype=np.float64)
elif gridType in ["reduced_ll", "reduced_gg"]:
self._x_points = self.longitudes
self._y_points = self.latitudes
else:
raise TranslationError("unhandled grid type")
