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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_attributes
#
# Description: how to read attributes of keys in BUFR 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')
cnt = 0
# define the attributes to be printed (see BUFR code table B)
attrs = [
'code',
'units',
'scale',
'reference',
'width'
]
# 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)
# --------------------------------------------------------------
# We will read the value and all the attributes available for
# the 2m temperature.
# --------------------------------------------------------------
# get the value
key = 'airTemperatureAt2M'
try:
print(' %s: %s' % (key, codes_get(bufr, key)))
except CodesInternalError as err:
print('Error with key="%s" : %s' % (key, err.msg))
# print the values of the attributes of the key. Attributes themselves
# are keys as well. Their name is constructed like:
# keyname->attributename
for attr in attrs:
key = 'airTemperatureAt2M' + "->" + attr
try:
print(' %s: %s' % (key, codes_get(bufr, key)))
except CodesInternalError as err:
print('Error with key="%s" : %s' % (key, err.msg))
# ------------------------------------------------------------------
# The 2m temperature data element in this message has an associated
# field: percentConfidence. Its value and attributes can be accessed
# in a similar manner as was shown above for 2m temperature.
# ------------------------------------------------------------------
# get the value
key = 'airTemperatureAt2M->percentConfidence'
try:
print(' %s: %s' % (key, codes_get(bufr, key)))
except CodesInternalError as err:
print('Error with key="%s" : %s' % (key, err.msg))
# print the values of the attributes of the key.
for attr in attrs:
key = 'airTemperatureAt2M->percentConfidence' + "->" + attr
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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