#!/usr/bin/env python
# -*- coding: utf-8 -*-
# Copyright (c) 2019 Satpy developers
#
# This file is part of satpy.
#
# satpy is free software: you can redistribute it and/or modify it under the
# terms of the GNU General Public License as published by the Free Software
# Foundation, either version 3 of the License, or (at your option) any later
# version.
#
# satpy is distributed in the hope that it will be useful, but WITHOUT ANY
# WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
# A PARTICULAR PURPOSE. See the GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License along with
# satpy. If not, see <http://www.gnu.org/licenses/>.
"""Geostationary Lightning Mapper reader for the Level 2 format from glmtools.
More information about `glmtools` and the files it produces can be found on
the project's GitHub repository:
https://github.com/deeplycloudy/glmtools
"""
import logging
from datetime import datetime
import numpy as np
from satpy.readers.abi_base import NC_ABI_BASE
logger = logging.getLogger(__name__)
PLATFORM_NAMES = {
'G16': 'GOES-16',
'G17': 'GOES-17',
'G18': 'GOES-18',
}
# class NC_GLM_L2_LCFA(BaseFileHandler): — add this with glmtools
[docs]class NCGriddedGLML2(NC_ABI_BASE):
"""File reader for individual GLM L2 NetCDF4 files."""
@property
def sensor(self):
"""Get sensor name for current file handler."""
return 'glm'
@property
def start_time(self):
"""Start time of the current file's observations."""
return datetime.strptime(self.nc.attrs['time_coverage_start'], '%Y-%m-%dT%H:%M:%SZ')
@property
def end_time(self):
"""End time of the current file's observations."""
return datetime.strptime(self.nc.attrs['time_coverage_end'], '%Y-%m-%dT%H:%M:%SZ')
def _is_category_product(self, data_arr):
# if after autoscaling we still have an integer
is_int = np.issubdtype(data_arr.dtype, np.integer)
# and it has a fill value
has_fill = '_FillValue' in data_arr.attrs
# or it has flag_meanings
has_meanings = 'flag_meanings' in data_arr.attrs
# then it is likely a category product and we should keep the
# _FillValue for satpy to use later
return is_int and (has_fill or has_meanings)
[docs] def get_dataset(self, key, info):
"""Load a dataset."""
logger.debug('Reading in get_dataset %s.', key['name'])
res = self[key['name']]
res.attrs.update({'platform_name': self.platform_name,
'sensor': self.sensor})
res.attrs.update(self.filename_info)
# Add orbital parameters
projection = self.nc["goes_imager_projection"]
res.attrs['orbital_parameters'] = {
'projection_longitude': float(projection.attrs['longitude_of_projection_origin']),
'projection_latitude': float(projection.attrs['latitude_of_projection_origin']),
'projection_altitude': float(projection.attrs['perspective_point_height']),
'satellite_nominal_latitude': float(self['nominal_satellite_subpoint_lat']),
'satellite_nominal_longitude': float(self['nominal_satellite_subpoint_lon']),
# 'satellite_nominal_altitude': float(self['nominal_satellite_height']),
}
res.attrs.update(key.to_dict())
# remove attributes that could be confusing later
if not self._is_category_product(res):
res.attrs.pop('_FillValue', None)
res.attrs.pop('scale_factor', None)
res.attrs.pop('add_offset', None)
res.attrs.pop('_Unsigned', None)
res.attrs.pop('ancillary_variables', None) # Can't currently load DQF
# add in information from the filename that may be useful to the user
# for key in ('observation_type', 'scene_abbr', 'scan_mode', 'platform_shortname'):
for attr in ('scene_abbr', 'scan_mode', 'platform_shortname'):
res.attrs[attr] = self.filename_info[attr]
# copy global attributes to metadata
for attr in ('scene_id', 'orbital_slot', 'instrument_ID',
'production_site', 'timeline_ID', 'spatial_resolution'):
res.attrs[attr] = self.nc.attrs.get(attr)
return res
def _is_2d_xy_var(self, data_arr):
is_2d = data_arr.ndim == 2
has_x_dim = 'x' in data_arr.dims
has_y_dim = 'y' in data_arr.dims
return is_2d and has_x_dim and has_y_dim
[docs] def available_datasets(self, configured_datasets=None):
"""Discover new datasets and add information from file."""
# we know the actual resolution
res = self.spatial_resolution_to_number()
# update previously configured datasets
handled_vars = set()
for is_avail, ds_info in (configured_datasets or []):
# some other file handler knows how to load this
# don't override what they've done
if is_avail is not None:
yield is_avail, ds_info
matches = self.file_type_matches(ds_info['file_type'])
if matches and ds_info.get('resolution') != res:
# we are meant to handle this dataset (file type matches)
# and the information we can provide isn't available yet
new_info = ds_info.copy()
new_info['resolution'] = res
exists = ds_info['name'] in self.nc
handled_vars.add(ds_info['name'])
yield exists, new_info
elif is_avail is None:
# we don't know what to do with this
# see if another future file handler does
yield is_avail, ds_info
for var_name, data_arr in self.nc.data_vars.items():
if var_name in handled_vars:
# it was manually configured and handled above
continue
if not self._is_2d_xy_var(data_arr):
# only handle 2d (y, x) vars for now
continue
new_info = {
'name': var_name,
'resolution': res,
'file_type': self.filetype_info['file_type']
}
handled_vars.add(var_name)
yield True, new_info