Source code for satpy.readers.eum_base

#!/usr/bin/env python
# -*- coding: utf-8 -*-
# Copyright (c) 2017-2018 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 <>.
"""Utilities for EUMETSAT satellite data."""

from datetime import datetime, timedelta

import numpy as np

# 6 bytes, 8 bytes, 10 bytes
time_cds_short = [("Days", ">u2"), ("Milliseconds", ">u4")]
time_cds = time_cds_short + [("Microseconds", ">u2")]
time_cds_expanded = time_cds + [("Nanoseconds", ">u2")]
issue_revision = [("Issue", np.uint16), ("Revision", np.uint16)]

[docs] def timecds2datetime(tcds): """Convert time_cds-variables to datetime-object. Works both with a dictionary and a numpy record_array. """ days = int(tcds["Days"].item()) milliseconds = int(tcds["Milliseconds"].item()) try: microseconds = int(tcds["Microseconds"].item()) except (KeyError, ValueError): microseconds = 0 try: microseconds += int(tcds["Nanoseconds"].item()) / 1000. except (KeyError, ValueError): pass reference = datetime(1958, 1, 1) delta = timedelta(days=days, milliseconds=milliseconds, microseconds=microseconds) return reference + delta
[docs] def recarray2dict(arr): """Convert numpy record array to a dictionary.""" res = {} tcds_types = [time_cds_short, time_cds, time_cds_expanded] for dtuple in arr.dtype.descr: key = dtuple[0] ntype = dtuple[1] data = arr[key] if ntype in tcds_types: if data.size > 1: res[key] = np.array([timecds2datetime(item) for item in data.ravel()]).reshape(data.shape) else: res[key] = timecds2datetime(data) elif isinstance(ntype, list): res[key] = recarray2dict(data) else: if data.size == 1: data = data[0] if ntype[:2] == "|S": # Python2 and Python3 handle strings differently try: data = data.decode() except ValueError: data = None else: data = data.split(":")[0].strip() res[key] = data else: res[key] = data.squeeze() return res
[docs] def get_service_mode(instrument_name, ssp_lon): """Get information about service mode for a given instrument and subsatellite longitude.""" service_modes = {"seviri": {"0.0": {"service_name": "fes", "service_desc": "Full Earth Scanning service"}, "9.5": {"service_name": "rss", "service_desc": "Rapid Scanning Service"}, "41.5": {"service_name": "iodc", "service_desc": "Indian Ocean Data Coverage service"}, "45.5": {"service_name": "iodc", "service_desc": "Indian Ocean Data Coverage service"} }, "fci": {"0.0": {"service_name": "fdss", "service_desc": "Full Disk Scanning Service"}, "9.5": {"service_name": "rss", "service_desc": "Rapid Scanning Service"}, }, } unknown_modes = {"service_name": "unknown", "service_desc": "unknown"} return service_modes.get(instrument_name, unknown_modes).get("{:.1f}".format(ssp_lon), unknown_modes)