eccodes/examples/python/index.py

84 lines
2.1 KiB
Python

#
# Copyright 2005-2014 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,os
from gribapi import *
INPUT='../../data/index.grib'
VERBOSE=1 # verbose error reporting
def product(*args, **kwds):
# product('ABCD', 'xy') --> Ax Ay Bx By Cx Cy Dx Dy
# product(range(2), repeat=3) --> 000 001 010 011 100 101 110 111
pools = map(tuple, args) * kwds.get('repeat', 1)
result = [[]]
for pool in pools:
result = [x+[y] for x in result for y in pool]
for prod in result:
yield tuple(prod)
def example():
index_keys = ["shortName","level","number","step"]
index_file = "my.idx"
iid = None
if (os.path.exists(index_file)):
iid = grib_index_read(index_file)
else:
iid = grib_index_new_from_file(INPUT,index_keys)
# multiple files can be added to an index:
# grib_index_add_file(iid,"grib file to add")
grib_index_write(iid,index_file)
index_vals = []
for key in index_keys:
print "%sSize=%d" % (
key,
grib_index_get_size(iid,key)
)
key_vals = grib_index_get(iid,key)
print " ".join(key_vals)
index_vals.append(key_vals)
for prod in product(*index_vals):
for i in range(len(index_keys)):
grib_index_select(iid,index_keys[i],prod[i])
while 1:
gid = grib_new_from_index(iid)
if gid is None: break
print " ".join(["%s=%s" % (key,grib_get(gid,key)) for key in index_keys])
grib_release(gid)
grib_index_release(iid)
def main():
try:
example()
except GribInternalError,err:
if VERBOSE:
traceback.print_exc(file=sys.stderr)
else:
print >>sys.stderr,err.msg
return 1
if __name__ == "__main__":
sys.exit(main())