# Copyright (c) 2022 Satpy developers
#
# 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/>.
"""Advanced Technology Microwave Sounder (ATMS) Level 1B product reader.
The format is explained in the `ATMS L1B Product User Guide`_
.. _`ATMS L1B Product User Guide`:
https://docserver.gesdisc.eosdis.nasa.gov/public/project/Sounder/ATMS_V3_L1B_Product_User_Guide.pdf
"""
import logging
from datetime import datetime
from satpy.readers.netcdf_utils import NetCDF4FileHandler
logger = logging.getLogger(__name__)
DATE_FMT = "%Y-%m-%dT%H:%M:%SZ"
[docs]
class AtmsL1bNCFileHandler(NetCDF4FileHandler):
"""Reader class for ATMS L1B products in netCDF format."""
def __init__(self, filename, filename_info, filetype_info, **kwargs):
"""Initialize file handler."""
super().__init__(
filename, filename_info, filetype_info, auto_maskandscale=True,
)
@property
def start_time(self):
"""Get observation start time."""
return datetime.strptime(self["/attr/time_coverage_start"], DATE_FMT)
@property
def end_time(self):
"""Get observation end time."""
return datetime.strptime(self["/attr/time_coverage_end"], DATE_FMT)
@property
def platform_name(self):
"""Get platform name."""
return self["/attr/platform"]
@property
def sensor(self):
"""Get sensor."""
return self["/attr/instrument"]
@property
def antenna_temperature(self):
"""Get antenna temperature."""
file_key = self.filetype_info["antenna_temperature"]
return self[file_key]
@property
def attrs(self):
"""Return attributes."""
return {
"filename": self.filename,
"start_time": self.start_time,
"end_time": self.end_time,
"platform_name": self.platform_name,
"sensor": self.sensor,
}
[docs]
@staticmethod
def _standardize_dims(dataset):
"""Standardize dims to y, x."""
if "atrack" in dataset.dims:
dataset = dataset.rename({"atrack": "y"})
if "xtrack" in dataset.dims:
dataset = dataset.rename({"xtrack": "x"})
if dataset.dims[0] == "x":
dataset = dataset.transpose("y", "x")
return dataset
[docs]
@staticmethod
def _drop_coords(dataset):
"""Drop coords that are not in dims."""
for coord in dataset.coords:
if coord not in dataset.dims:
dataset = dataset.drop_vars(coord)
return dataset
[docs]
def _merge_attributes(self, dataset, dataset_info):
"""Merge attributes of the dataset."""
dataset.attrs.update(self.filename_info)
dataset.attrs.update(dataset_info)
dataset.attrs.update(self.attrs)
return dataset
[docs]
def _select_dataset(self, name):
"""Select dataset."""
try:
idx = int(name) - 1
return self.antenna_temperature[:, :, idx]
except ValueError:
return self[name]
[docs]
def get_dataset(self, dataset_id, ds_info):
"""Get dataset."""
name = dataset_id["name"]
logger.debug(f"Reading in file to get dataset with name {name}.")
dataset = self._select_dataset(name)
dataset = self._merge_attributes(dataset, ds_info)
dataset = self._drop_coords(dataset)
return self._standardize_dims(dataset)