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# (C) Copyright 2005- ECMWF.
#
# This software is licensed under the terms of the Apache Licence Version 2.0
# which can be obtained at http://www.apache.org/licenses/LICENSE-2.0.
#
# In applying this licence, ECMWF does not waive the privileges and immunities
# granted to it by virtue of its status as an intergovernmental organisation
# nor does it submit to any jurisdiction.
#
# Python implementation: bufr_read_synop
#
# Description: how to read data values from BUFR messages.
#
# Please note that SYNOP reports can be encoded in various ways in BUFR.
# Therefore the code below might not work directly for other types of SYNOP
# messages than the one used in the example. It is advised to use bufr_dump to
# understand the structure of the messages.
from __future__ import print_function
import traceback
import sys
from eccodes import *
INPUT = '../../data/bufr/syno_multi.bufr'
VERBOSE = 1 # verbose error reporting
def example():
# open bufr file
f = open(INPUT, 'rb')
# define the keys to be printed
keys = [
'blockNumber',
'stationNumber',
'latitude',
'longitude',
'airTemperatureAt2M',
'dewpointTemperatureAt2M',
'windSpeedAt10M',
'windDirectionAt10M',
'#1#cloudAmount', # cloud amount (low and mid level)
'#1#heightOfBaseOfCloud',
'#1#cloudType', # cloud type (low clouds)
'#2#cloudType', # cloud type (middle clouds)
'#3#cloudType' # cloud type (highclouds)
]
# The cloud information is stored in several blocks in the
# SYNOP message and the same key means a different thing in different
# parts of the message. In this example we will read the first
# cloud block introduced by the key
# verticalSignificanceSurfaceObservations=1.
# We know that this is the first occurrence of the keys we want to
# read so in the list above we used the # (occurrence) operator
# accordingly.
cnt = 0
# loop for the messages in the file
while 1:
# get handle for message
bufr = codes_bufr_new_from_file(f)
if bufr is None:
break
print("message: %s" % cnt)
# we need to instruct ecCodes to expand all the descriptors
# i.e. unpack the data values
codes_set(bufr, 'unpack', 1)
# print the values for the selected keys from the message
for key in keys:
try:
print(' %s: %s' % (key, codes_get(bufr, key)))
except CodesInternalError as err:
print('Error with key="%s" : %s' % (key, err.msg))
cnt += 1
# delete handle
codes_release(bufr)
# close the file
f.close()
def main():
try:
example()
except CodesInternalError as err:
if VERBOSE:
traceback.print_exc(file=sys.stderr)
else:
sys.stderr.write(err.msg + '\n')
return 1
if __name__ == "__main__":
sys.exit(main())
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