eccodes/examples/python/grib_set_keys.py

# Copyright 2005-2016 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.

import traceback
import sys

from eccodes import *
from datetime import date

INPUT = '../../data/regular_latlon_surface_constant.grib1'
OUTPUT = 'out.set.grib'
VERBOSE = 1  # verbose error reporting


def example():
    fin = open(INPUT)
    fout = open(OUTPUT, 'w')
    gid = codes_grib_new_from_file(fin)

    dt = date.today()
    today = "%d%02d%02d" % (dt.year, dt.month, dt.day)
    codes_set(gid, 'dataDate', int(today))
    codes_set(gid, 'centre', 80)

    centreIntVal = codes_get_array(gid, 'centre', int)
    centreStrVal = codes_get_array(gid, 'centre', str)
    dateStrVal = codes_get_array(gid, 'dataDate', str)
    assert(centreIntVal[0] == 80)
    assert(centreStrVal[0] == 'cnmc')
    assert(dateStrVal[0] == today)
    print 'get centre as an integer - centre = %d' % centreIntVal[0]
    print 'get centre as a string - centre = %s' % centreStrVal[0]
    print 'get date as a string - date = %s' % dateStrVal[0]

    # Now do the same but using set_key_vals, setting keys all at once
    codes_set_key_vals(gid, 'level=1,centre=98')  # with a String
    assert(codes_get(gid, 'centre', str) == 'ecmf')
    assert(codes_get(gid, 'level', int) == 1)

    codes_set_key_vals(gid, ['level=2', 'centre=kwbc'])  # with a Tuple
    assert(codes_get(gid, 'centre', int) == 7)
    assert(codes_get(gid, 'level', int) == 2)

    codes_set_key_vals(gid, {'level': 3, 'centre': 84})  # with a Dictionary
    assert(codes_get(gid, 'centre', str) == 'lfpw')
    assert(codes_get(gid, 'level', int) == 3)

    codes_gts_header(True)
    codes_gts_header(False)

    codes_write(gid, fout)
    codes_release(gid)
    fin.close()
    fout.close()


def main():
    try:
        example()
    except CodesInternalError, err:
        if VERBOSE:
            traceback.print_exc(file=sys.stderr)
        else:
            print >>sys.stderr, err.msg

        return 1

if __name__ == "__main__":
    sys.exit(main())