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744 lines
28 KiB
744 lines
28 KiB
from __future__ import (absolute_import, division, print_function, |
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unicode_literals) |
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import numpy as np |
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import math |
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|
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from .config import basemap_enabled, cartopy_enabled, pyngl_enabled |
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from .constants import Constants |
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|
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if cartopy_enabled(): |
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from cartopy import crs |
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|
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if basemap_enabled(): |
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from mpl_toolkits.basemap import Basemap |
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|
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if pyngl_enabled(): |
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from Ngl import Resources |
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if cartopy_enabled(): |
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class MercatorWithLatTS(crs.Mercator): |
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def __init__(self, central_longitude=0.0, |
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latitude_true_scale=0.0, |
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min_latitude=-80.0, |
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max_latitude=84.0, |
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globe=None): |
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proj4_params = [("proj", "merc"), |
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("lon_0", central_longitude), |
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("lat_ts", latitude_true_scale), |
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("k", 1), |
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("units", "m")] |
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super(crs.Mercator, self).__init__(proj4_params, globe=globe) |
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|
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# Calculate limits. |
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limits = self.transform_points(crs.Geodetic(), |
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np.array([-180, 180]) + central_longitude, |
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np.array([min_latitude, max_latitude])) |
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# When using a latitude of true scale, the min/max x-limits get set |
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# to the same value, so make sure the left one is negative |
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xlimits = limits[..., 0] |
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|
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if xlimits[0] == xlimits[1]: |
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if xlimits[0] < 0: |
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xlimits[1] = -xlimits[1] |
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else: |
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xlimits[0] = -xlimits[0] |
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self._xlimits = tuple(xlimits) |
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self._ylimits = tuple(limits[..., 1]) |
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self._threshold = np.diff(self.x_limits)[0] / 720 |
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def _ismissing(val): |
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return val is None or val > 90. or val < -90. |
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|
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class WrfProj(object): |
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def __init__(self, bottom_left=None, top_right=None, |
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lats=None, lons=None, **proj_params): |
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if bottom_left is not None and top_right is not None: |
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self.ll_lat = bottom_left[0] |
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self.ll_lon = bottom_left[1] |
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self.ur_lat = top_right[0] |
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self.ur_lon = top_right[1] |
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self.bottom_left = bottom_left |
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self.top_right = top_right |
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elif lats is not None and lons is not None: |
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self.ll_lat = lats[0,0] |
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self.ur_lat = lats[-1,-1] |
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self.ll_lon = lons[0,0] |
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self.ur_lon = lons[-1,-1] |
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self.bottom_left = [self.ll_lat, self.ll_lon] |
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self.top_right = [self.ur_lat, self.ur_lon] |
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else: |
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raise ValueError("invalid corner point arguments") |
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# These indicate the center of the nest/domain, not necessarily the |
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# center of the projection |
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self._cen_lat = proj_params.get("CEN_LAT", None) |
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self._cen_lon = proj_params.get("CEN_LON", None) |
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self.truelat1 = proj_params.get("TRUELAT1", None) |
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self.truelat2 = (proj_params.get("TRUELAT2", None) |
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if not _ismissing(proj_params.get("TRUELAT2", None)) |
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else None) |
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self.moad_cen_lat = proj_params.get("MOAD_CEN_LAT", None) |
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self.stand_lon = proj_params.get("STAND_LON", None) |
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self.pole_lat = proj_params.get("POLE_LAT", None) |
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self.pole_lon = proj_params.get("POLE_LON", None) |
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# Just in case... |
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if self.moad_cen_lat is None: |
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self.moad_cen_lat = self._cen_lat |
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if self.stand_lon is None: |
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self.stand_lon = self._cen_lon |
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def _basemap(self, resolution='l'): |
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return None |
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def _cf_params(self): |
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return None |
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def _cartopy(self): |
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return None |
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def _cart_extents(self): |
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return ([self.ll_lon, self.ur_lon], [self.ll_lat, self.ur_lat]) |
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def _pyngl(self): |
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return None |
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def _proj4(self): |
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return None |
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def _globe(self): |
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return (None if not cartopy_enabled() |
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else crs.Globe(ellipse=None, |
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semimajor_axis=Constants.WRF_EARTH_RADIUS, |
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semiminor_axis=Constants.WRF_EARTH_RADIUS)) |
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def cartopy_xlim(self): |
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"""Return the x extents in projected coordinates (for cartopy)""" |
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return self._cart_extents()[0] |
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def cartopy_ylim(self): |
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"""Return the y extents in projected coordinates (for cartopy)""" |
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return self._cart_extents()[1] |
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|
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def __repr__(self): |
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args = ("bottom_left={}, top_right={}, " |
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"stand_lon={}, moad_cen_lat={}, " |
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"pole_lat={}, pole_lon={}".format((self.ll_lat, self.ll_lon), |
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(self.ur_lat, self.ur_lon), |
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self.stand_lon, |
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self.moad_cen_lat, |
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self.pole_lat, |
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self.pole_lon)) |
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return "{}({})".format(self.__class__.__name__, args) |
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def basemap(self, resolution='l'): |
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"""Return a mpl_toolkits.basemap.Basemap instance for the |
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projection""" |
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if not basemap_enabled(): |
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raise RuntimeError("'mpl_toolkits.basemap' is not " |
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"installed or is disabled") |
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return self._basemap(resolution) |
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def cartopy(self): |
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"""Return a cartopy.crs.Projection subclass for the |
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projection""" |
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if not cartopy_enabled(): |
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raise RuntimeError("'cartopy' is not " |
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"installed or is disabled") |
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return self._cartopy() |
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def pyngl(self): |
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"""Return the PyNGL resources for the projection""" |
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if not pyngl_enabled(): |
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raise RuntimeError("'pyngl' is not " |
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"installed or is disabled") |
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return self._pyngl() |
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def proj4(self): |
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"""Return the proj4 string for the map projection""" |
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return self._proj4() |
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def cf(self): |
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"""Return a dictionary with the NetCDF CF parameters for the |
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projection""" |
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return self._cf_params() |
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# Used for 'missing' projection values during the 'join' method |
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class NullProjection(WrfProj): |
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def __init__(self): |
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pass |
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def __repr__(self): |
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return "{}()".format(self.__class__.__name__) |
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class LambertConformal(WrfProj): |
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def __init__(self, bottom_left=None, top_right=None, |
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lats=None, lons=None, **proj_params): |
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super(LambertConformal, self).__init__(bottom_left, |
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top_right, lats, lons, **proj_params) |
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self._std_parallels = [self.truelat1] |
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if self.truelat2 is not None: |
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self._std_parallels.append(self.truelat2) |
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def _cf_params(self): |
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_cf_params = {} |
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_cf_params["grid_mapping_name"] = "lambert_conformal_conic"; |
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_cf_params["standard_parallel"] = self._std_parallels |
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_cf_params["longitude_of_central_meridian"] = self.stand_lon |
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_cf_params["latitude_of_projection_origin"] = self.moad_cen_lat |
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_cf_params["semi_major_axis"] = Constants.WRF_EARTH_RADIUS |
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return _cf_params |
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def _pyngl(self): |
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if not pyngl_enabled(): |
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return None |
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truelat2 = (self.truelat1 |
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if _ismissing(self.truelat2) |
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else self.truelat2) |
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_pyngl = Resources() |
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_pyngl.mpProjection = "LambertConformal" |
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_pyngl.mpDataBaseVersion = "MediumRes" |
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_pyngl.mpLimitMode = "Corners" |
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_pyngl.mpLeftCornerLonF = self.ll_lon |
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_pyngl.mpLeftCornerLatF = self.ll_lat |
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_pyngl.mpRightCornerLonF = self.ur_lon |
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_pyngl.mpRightCornerLatF = self.ur_lat |
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_pyngl.mpLambertMeridianF = self.stand_lon |
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_pyngl.mpLambertParallel1F = self.truelat1 |
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_pyngl.mpLambertParallel2F = truelat2 |
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return _pyngl |
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def _basemap(self, resolution='l'): |
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if not basemap_enabled(): |
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return None |
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_basemap = Basemap(projection = "lcc", |
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lon_0 = self.stand_lon, |
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lat_0 = self.moad_cen_lat, |
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lat_1 = self.truelat1, |
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lat_2 = self.truelat2, |
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llcrnrlat = self.ll_lat, |
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urcrnrlat = self.ur_lat, |
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llcrnrlon = self.ll_lon, |
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urcrnrlon = self.ur_lon, |
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rsphere = Constants.WRF_EARTH_RADIUS, |
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resolution = resolution) |
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return _basemap |
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def _cartopy(self): |
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if not cartopy_enabled(): |
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return None |
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_cartopy = crs.LambertConformal( |
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central_longitude = self.stand_lon, |
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central_latitude = self.moad_cen_lat, |
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standard_parallels = self._std_parallels, |
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globe = self._globe()) |
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return _cartopy |
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def _cart_extents(self): |
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# Need to modify the extents for the new projection |
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pc = crs.PlateCarree() |
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xs, ys, zs = self._cartopy.transform_points(pc, |
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np.array([self.ll_lon, self.ur_lon]), |
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np.array([self.ll_lat, self.ur_lat])).T |
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_xlimits = xs.tolist() |
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_ylimits = ys.tolist() |
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return (_xlimits, _ylimits) |
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def _proj4(self): |
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truelat2 = (self.truelat1 |
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if _ismissing(self.truelat2) |
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else self.truelat2) |
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_proj4 = ("+proj=lcc +units=meters +a={} +b={} +lat_1={} " |
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"+lat_2={} +lat_0={} +lon_0={}".format( |
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Constants.WRF_EARTH_RADIUS, |
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Constants.WRF_EARTH_RADIUS, |
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self.truelat1, |
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truelat2, |
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self.moad_cen_lat, |
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self.stand_lon)) |
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return _proj4 |
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class Mercator(WrfProj): |
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def __init__(self, bottom_left=None, top_right=None, |
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lats=None, lons=None, **proj_params): |
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super(Mercator, self).__init__(bottom_left, top_right, |
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lats, lons, **proj_params) |
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self._lat_ts = (None |
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if self.truelat1 == 0. or _ismissing(self.truelat1) |
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else self.truelat1) |
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def _cf_params(self): |
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_cf_params = {} |
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_cf_params["grid_mapping_name"] = "mercator" |
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_cf_params["longitude_of_projection_origin"] = self.stand_lon |
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_cf_params["standard_parallel"] = self.truelat1 |
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return _cf_params |
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def _pyngl(self): |
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if not pyngl_enabled(): |
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return None |
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_pyngl = Resources() |
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_pyngl.mpProjection = "Mercator" |
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_pyngl.mpDataBaseVersion = "MediumRes" |
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_pyngl.mpLimitMode = "Corners" |
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_pyngl.mpLeftCornerLonF = self.ll_lon |
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_pyngl.mpLeftCornerLatF = self.ll_lat |
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_pyngl.mpRightCornerLonF = self.ur_lon |
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_pyngl.mpRightCornerLatF = self.ur_lat |
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_pyngl.mpCenterLatF = 0.0 |
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_pyngl.mpCenterLonF = self.stand_lon |
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return _pyngl |
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def _basemap(self, resolution='l'): |
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if not basemap_enabled(): |
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return None |
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_basemap = Basemap(projection = "merc", |
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lon_0 = self.stand_lon, |
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lat_0 = self.moad_cen_lat, |
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lat_ts = self._lat_ts, |
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llcrnrlat = self.ll_lat, |
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urcrnrlat = self.ur_lat, |
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llcrnrlon = self.ll_lon, |
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urcrnrlon = self.ur_lon, |
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rsphere = Constants.WRF_EARTH_RADIUS, |
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resolution = resolution) |
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return _basemap |
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def _cartopy(self): |
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if not cartopy_enabled(): |
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return None |
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if self._lat_ts == 0.0: |
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_cartopy = crs.Mercator( |
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central_longitude = self.stand_lon, |
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globe = self._globe()) |
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else: |
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_cartopy = MercatorWithLatTS( |
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central_longitude = self.stand_lon, |
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latitude_true_scale = self._lat_ts, |
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globe = self._globe()) |
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return _cartopy |
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def _cart_extents(self): |
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|
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# Need to modify the extents for the new projection |
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pc = crs.PlateCarree() |
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xs, ys, zs = self._cartopy.transform_points(pc, |
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np.array([self.ll_lon, self.ur_lon]), |
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np.array([self.ll_lat, self.ur_lat])).T |
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_xlimits = xs.tolist() |
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_ylimits = ys.tolist() |
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return (_xlimits, _ylimits) |
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def _proj4(self): |
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_proj4 = ("+proj=merc +units=meters +a={} +b={} " |
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"+lon_0={} +lat_ts={}".format( |
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Constants.WRF_EARTH_RADIUS, |
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Constants.WRF_EARTH_RADIUS, |
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self.stand_lon, |
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self._lat_ts)) |
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return _proj4 |
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class PolarStereographic(WrfProj): |
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def __init__(self, bottom_left=None, top_right=None, |
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lats=None, lons=None, **proj_params): |
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super(PolarStereographic, self).__init__(bottom_left, |
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top_right, lats, lons, **proj_params) |
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self._hemi = -90. if self.truelat1 < 0 else 90. |
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self._lat_ts = (None |
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if _ismissing(self.truelat1) |
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else self.truelat1) |
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def _cf_params(self): |
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_cf_params = {} |
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_cf_params["grid_mapping_name"] = "polar_stereographic" |
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_cf_params["straight_vertical_longitude_from_pole"] = ( |
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self.stand_lon) |
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_cf_params["standard_parallel"] = self.truelat1 |
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_cf_params["latitude_of_projection_origin"] = self._hemi |
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return _cf_params |
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def _pyngl(self): |
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if not pyngl_enabled(): |
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return None |
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_pyngl = Resources() |
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_pyngl.mpProjection = "Stereographic" |
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_pyngl.mpDataBaseVersion = "MediumRes" |
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_pyngl.mpLimitMode = "Corners" |
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_pyngl.mpLeftCornerLonF = self.ll_lon |
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_pyngl.mpLeftCornerLatF = self.ll_lat |
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_pyngl.mpRightCornerLonF = self.ur_lon |
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_pyngl.mpRightCornerLatF = self.ur_lat |
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_pyngl.mpCenterLonF = self.stand_lon |
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if self._hemi > 0: |
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_pyngl.mpCenterLatF = 90.0 |
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else: |
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_pyngl.mpCenterLatF = -90.0 |
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return _pyngl |
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def _basemap(self, resolution='l'): |
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if not basemap_enabled(): |
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return None |
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_basemap = Basemap(projection = "stere", |
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lon_0 = self.stand_lon, |
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lat_0 = self._hemi, |
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lat_ts = self._lat_ts, |
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llcrnrlat = self.ll_lat, |
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urcrnrlat = self.ur_lat, |
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llcrnrlon = self.ll_lon, |
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urcrnrlon = self.ur_lon, |
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rsphere = Constants.WRF_EARTH_RADIUS, |
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resolution = resolution) |
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return _basemap |
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def _cartopy(self): |
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if not cartopy_enabled(): |
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return None |
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_cartopy = crs.Stereographic(central_latitude=self._hemi, |
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central_longitude=self.stand_lon, |
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true_scale_latitude=self._lat_ts, |
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globe=self._globe()) |
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return _cartopy |
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def _cart_extents(self): |
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# Need to modify the extents for the new projection |
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pc = crs.PlateCarree() |
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xs, ys, zs = self._cartopy.transform_points(pc, |
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np.array([self.ll_lon, self.ur_lon]), |
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np.array([self.ll_lat, self.ur_lat])).T |
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|
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_xlimits = xs.tolist() |
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_ylimits = ys.tolist() |
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return (_xlimits, _ylimits) |
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def _proj4(self): |
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_proj4 = ("+proj=stere +units=meters +a={} +b={} " |
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"+lat0={} +lon_0={} +lat_ts={}".format( |
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Constants.WRF_EARTH_RADIUS, |
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Constants.WRF_EARTH_RADIUS, |
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self._hemi, |
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self.stand_lon, |
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self._lat_ts)) |
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return _proj4 |
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class LatLon(WrfProj): |
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def __init__(self, bottom_left=None, top_right=None, |
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lats=None, lons=None, **proj_params): |
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super(LatLon, self).__init__(bottom_left, top_right, |
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lats, lons, **proj_params) |
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def _cf_params(self): |
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_cf_params = {} |
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_cf_params["grid_mapping_name"] = "latitude_longitude" |
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return _cf_params |
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def _pyngl(self): |
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if not pyngl_enabled(): |
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return None |
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_pyngl = Resources() |
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_pyngl.mpProjection = "CylindricalEquidistant" |
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_pyngl.mpDataBaseVersion = "MediumRes" |
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_pyngl.mpLimitMode = "Corners" |
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_pyngl.mpLeftCornerLonF = self.ll_lon |
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_pyngl.mpLeftCornerLatF = self.ll_lat |
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_pyngl.mpRightCornerLonF = self.ur_lon |
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_pyngl.mpRightCornerLatF = self.ur_lat |
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_pyngl.mpCenterLonF = self.stand_lon |
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_pyngl.mpCenterLatF = self.moad_cen_lat |
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|
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return _pyngl |
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|
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def _basemap(self, resolution='l'): |
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if not basemap_enabled(): |
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return None |
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_basemap = Basemap(projection = "cyl", |
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lon_0 = self.stand_lon, |
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lat_0 = self.moad_cen_lat, |
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llcrnrlat = self.ll_lat, |
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urcrnrlat = self.ur_lat, |
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llcrnrlon = self.ll_lon, |
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urcrnrlon = self.ur_lon, |
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rsphere = Constants.WRF_EARTH_RADIUS, |
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resolution = resolution) |
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|
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return _basemap |
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|
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def _cartopy(self): |
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if not cartopy_enabled(): |
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return None |
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|
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_cartopy = crs.PlateCarree(central_longitude=self.stand_lon, |
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globe=self._globe()) |
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|
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return _cartopy |
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|
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def _cart_extents(self): |
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return ([self.ll_lon, self.ur_lon], [self.ll_lat, self.ur_lat]) |
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|
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def _proj4(self): |
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_proj4 = ("+proj=eqc +units=meters +a={} +b={} " |
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"+lon_0={}".format(Constants.WRF_EARTH_RADIUS, |
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Constants.WRF_EARTH_RADIUS, |
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self.stand_lon)) |
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return _proj4 |
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|
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# Notes (may not be correct since this projection confuses me): |
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# Each projection system handles this differently. |
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# 1) In WRF, if following the WPS instructions, POLE_LON is mainly used to |
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# determine north or south hemisphere. In other words, it determines if |
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# the globe is tipped toward or away from you. |
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# 2) In WRF, POLE_LAT is always positive, but should be negative in the |
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# proj4 based systems when using the southern hemisphere projections. |
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# 3) In cartopy, pole_longitude is used to describe the dateline, which |
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# is 180 degrees away from the normal central (standard) longitude |
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# (e.g. center of the projection), according to the cartopy developer. |
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# 4) In basemap, lon_0 should be set to the central (standard) longitude. |
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# 5) In either cartopy, basemap or pyngl, I'm not sure that projections with |
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# a pole_lon not equal to 0 or 180 can be plotted. Hopefully people |
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# follow the WPS instructions, otherwise I need to see a sample file and |
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# a lot of rum. |
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# 6) For items in 3 - 4, the "longitude" (lon_0 or pole_longitude) is |
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# determined by WRF's |
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# STAND_LON values, with the following calculations based on hemisphere: |
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# BASEMAP: NH: -STAND_LON; SH: 180.0 - STAND_LON |
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# CARTOPY: NH: -STAND_LON - 180.; SH: -STAND_LON |
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# 9) For PYNGL/NCL, you only need to set the center lat and center lon, |
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# Center lat is the offset of the pole from +/- 90 degrees. Center |
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# lon is -STAND_LON in NH and 180.0 - STAND_LON in SH. |
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# 10) It also appears that NetCDF CF has no clear documentation on what |
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# each parameter means. Going to assume it is the same as basemap, since |
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# basemap appears to mirror the WMO way of doing things (tilt earth, then |
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# spin globe). |
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# 11) Basemap and cartopy produce projections that differ in their extent |
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# calculations by either using negative values or 0-360 (basemap). For |
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# this reason, the proj4 string for this class will use cartopy's values |
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# to keep things in the -180 to 180, -90 to 90 range. |
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# 12) This projection makes me sad. |
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class RotatedLatLon(WrfProj): |
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def __init__(self, bottom_left=None, top_right=None, |
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lats=None, lons=None, **proj_params): |
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super(RotatedLatLon, self).__init__(bottom_left, top_right, |
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lats, lons, **proj_params) |
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|
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# Need to determine hemisphere, typically pole_lon is 0 for southern |
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# hemisphere, 180 for northern hemisphere. If not, going to have |
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# to guess based on other parameters, but hopefully people follow |
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# the WPS instructions and this never happens. |
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self._north = True |
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if self.pole_lon is not None: |
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if self.pole_lon == 0.: |
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self._north = False |
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elif self.pole_lon != 180.: |
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if self.moad_cen_lat is not None and self.moad_cen_lat < 0.0: |
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# Only probably true |
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self._north = False |
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else: |
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if self.moad_cen_lat is not None and self.moad_cen_lat < 0.0: |
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# Only probably true |
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self._north = False |
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if self.pole_lat is not None and self.stand_lon is not None: |
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self._pyngl_cen_lat = (90. - self.pole_lat if self._north |
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else self.pole_lat - 90.0) |
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self._pyngl_cen_lon = (-self.stand_lon if self._north |
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else 180.0 - self.stand_lon) |
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self._bm_lon_0 = (-self.stand_lon if self._north |
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else 180.0 - self.stand_lon) |
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self._bm_cart_pole_lat = (self.pole_lat if self._north |
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else -self.pole_lat ) |
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# The important point is that pole longitude is the position |
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# of the dateline of the new projection, not its central |
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# longitude (per the creator of cartopy). This is based on |
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# how it's handled by agencies like WMO, but not proj4. |
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self._cart_pole_lon = (-self.stand_lon - 180.0 if self._north |
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else -self.stand_lon) |
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else: |
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self._pyngl_cen_lat = self.moad_cen_lat |
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self._pyngl_cen_lon = self.stand_lon |
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self._bm_cart_pole_lat = (90.0 - self.moad_cen_lat if self._north |
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else -90.0 - self.moad_cen_lat) |
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self._bm_lon_0 = (-self.stand_lon if self._north |
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else 180.0 - self.stand_lon) |
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self._cart_pole_lon = (-self.stand_lon - 180.0 if self._north |
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else -self.stand_lon) |
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|
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def _cf_params(self): |
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_cf_params = {} |
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# Assuming this follows the same guidelines as cartopy |
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_cf_params["grid_mapping_name"] = "rotated_latitude_longitude" |
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_cf_params["grid_north_pole_latitude"] = self._bm_cart_pole_lat |
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_cf_params["grid_north_pole_longitude"] = self.pole_lon |
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_cf_params["north_pole_grid_longitude"] = self._bm_lon_0 |
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return _cf_params |
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|
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def _pyngl(self): |
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if not pyngl_enabled(): |
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return None |
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|
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_pyngl = Resources() |
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_pyngl.mpProjection = "CylindricalEquidistant" |
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_pyngl.mpDataBaseVersion = "MediumRes" |
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_pyngl.mpLimitMode = "Corners" |
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_pyngl.mpLeftCornerLonF = self.ll_lon |
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_pyngl.mpLeftCornerLatF = self.ll_lat |
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_pyngl.mpRightCornerLonF = self.ur_lon |
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_pyngl.mpRightCornerLatF = self.ur_lat |
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_pyngl.mpCenterLatF = self._pyngl_cen_lat |
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_pyngl.mpCenterLonF = self._pyngl_cen_lon |
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|
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return _pyngl |
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|
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def _basemap(self, resolution='l'): |
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if not basemap_enabled(): |
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return None |
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|
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_basemap = Basemap(projection = "rotpole", |
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o_lat_p = self._bm_cart_pole_lat, |
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o_lon_p = self.pole_lon, |
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llcrnrlat = self.ll_lat, |
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urcrnrlat = self.ur_lat, |
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llcrnrlon = self.ll_lon, |
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urcrnrlon = self.ur_lon, |
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lon_0 = self._bm_lon_0, |
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rsphere = Constants.WRF_EARTH_RADIUS, |
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resolution = resolution) |
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return _basemap |
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|
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def _cartopy(self): |
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if not cartopy_enabled(): |
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return None |
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|
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_cartopy = crs.RotatedPole( |
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pole_longitude=self._cart_pole_lon, |
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pole_latitude=self._bm_cart_pole_lat, |
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central_rotated_longitude=( |
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180.0 - self.pole_lon), # Probably |
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globe = self._globe()) |
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return _cartopy |
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def _cart_extents(self): |
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# Need to modify the extents for the new projection |
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pc = crs.PlateCarree() |
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xs, ys, zs = self._cartopy.transform_points(pc, |
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np.array([self.ll_lon, self.ur_lon]), |
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np.array([self.ll_lat, self.ur_lat])).T |
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_xlimits = xs.tolist() |
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_ylimits = ys.tolist() |
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return (_xlimits, _ylimits) |
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def _proj4(self): |
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_proj4 = ("+proj=ob_tran +o_proj=latlon " |
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"+a={} +b={} +to_meter={} +o_lon_p={} +o_lat_p={} " |
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"+lon_0={}".format(Constants.WRF_EARTH_RADIUS, |
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Constants.WRF_EARTH_RADIUS, |
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math.radians(1), |
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180.0 - self.pole_lon, |
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self._bm_cart_pole_lat, |
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180.0 + self._cart_pole_lon)) |
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return _proj4 |
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|
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def getproj(bottom_left=None, top_right=None, |
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lats=None, lons=None, **proj_params): |
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|
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proj_type = proj_params.get("MAP_PROJ", 0) |
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if proj_type == 1: |
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return LambertConformal(bottom_left, top_right, |
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lats, lons, **proj_params) |
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elif proj_type == 2: |
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return PolarStereographic(bottom_left, top_right, |
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lats, lons, **proj_params) |
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elif proj_type == 3: |
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return Mercator(bottom_left, top_right, |
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lats, lons, **proj_params) |
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elif proj_type == 0 or proj_type == 6: |
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if (proj_params.get("POLE_LAT", None) == 90. |
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and proj_params.get("POLE_LON", None) == 0.): |
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return LatLon(bottom_left, top_right, |
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lats, lons, **proj_params) |
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else: |
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return RotatedLatLon(bottom_left, top_right, |
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lats, lons, **proj_params) |
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else: |
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# Unknown projection |
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return WrfProj(bottom_left, top_right, |
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lats, lons, **proj_params) |
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