eccodes/examples/python/grib_set_pv.py

#
# (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.
#

import sys
import traceback

from eccodes import *

VERBOSE = 1  # verbose error reporting


def example():
    """
    Encoding of the pv coefficients.
    """
    # read the coefficients from file
    pv = []
    for line in open("../../data/60_model_levels"):
        pv.extend([float(x) for x in line.strip().split("\t")])

    numberOfLevels = 60
    numberOfCoefficients = 2 * (numberOfLevels + 1)
    assert len(pv) == numberOfCoefficients

    fout = open("grib_set_pv.py.temp.grib", "wb")
    gid = codes_grib_new_from_samples("reduced_gg_sfc_grib1")

    codes_set(gid, "typeOfLevel", "hybrid")
    codes_set(gid, "level", 2)
    codes_set(gid, "PVPresent", 1)
    codes_set_array(gid, "pv", pv)

    codes_write(gid, fout)

    codes_release(gid)
    fout.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())