Description
This example shows: how to read values of different type of keys from BUFR messages.Source code
bufr_get_keys.f90
! !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. ! ! ! FORTRAN 90 Implementation: bufr_get_keys ! ! Description: how to read values of different type of keys from BUFR messages. ! ! program bufr_get_keys use eccodes implicit none integer :: ifile integer :: iret integer :: ibufr integer :: i, count=0 integer(kind=4) :: blockNumber,stationNumber real(kind=8) :: t2m integer(kind=4), dimension(:), allocatable :: descriptors real(kind=8), dimension(:), allocatable :: values character(len=9) :: typicalDate call codes_open_file(ifile,'../../data/bufr/syno_multi.bufr','r') ! the first bufr message is loaded from file ! ibufr is the bufr id to be used in subsequent calls call codes_bufr_new_from_file(ifile,ibufr,iret) do while (iret/=CODES_END_OF_FILE) ! For debugging call codes_dump(ibufr) ! get and print some keys form the BUFR header write(*,*) 'message: ',count ! we need to instruct ecCodes to expand all the descriptors ! i.e. unpack the data values call codes_set(ibufr,"unpack",1); ! get as character call codes_get(ibufr,'typicalDate',typicalDate) write(*,*) ' typicalDate:',typicalDate ! get as integer call codes_get(ibufr,'blockNumber',blockNumber); write(*,*) ' blockNumber:',blockNumber ! get as integer call codes_get(ibufr,'stationNumber',stationNumber); write(*,*) ' stationNumber:',stationNumber ! get as real call codes_get(ibufr,'airTemperatureAt2M',t2m); write(*,*) ' airTemperatureAt2M:',t2m ! ---- array of integer ---------------- ! get the expanded descriptors call codes_get(ibufr,'bufrdcExpandedDescriptors',descriptors) do i=1,size(descriptors) write(*,*) ' ',i,descriptors(i) enddo ! ---- array of real ---------------- ! get the expanded data values call codes_get(ibufr,'numericValues',values) do i=1,size(values) write(*,*) ' ',i,values(i) enddo ! get as character call codes_get(ibufr,'typicalDate',typicalDate) write(*,*) ' typicalDate:',typicalDate ! free arrays deallocate(values) deallocate(descriptors) ! release the bufr message call codes_release(ibufr) ! load the next bufr message call codes_bufr_new_from_file(ifile,ibufr,iret) count=count+1 end do ! close file call codes_close_file(ifile) end program bufr_get_keys
bufr_get_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. # # Python implementation: bufr_get_keys # # Description: how to read values of different type of keys from BUFR messages. # # 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) 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) # --------------------------------------------- # get values for keys holding a single value # --------------------------------------------- # Native type integer key = 'blockNumber' try: print ' %s: %s' % (key, codes_get(bufr, key)) except CodesInternalError as err: print 'Error with key="%s" : %s' % (key, err.msg) # Native type integer key = 'stationNumber' try: print ' %s: %s' % (key, codes_get(bufr, key)) except CodesInternalError as err: print 'Error with key="%s" : %s' % (key, err.msg) # Native type float key = 'airTemperatureAt2M' try: print ' %s: %s' % (key, codes_get(bufr, key)) except CodesInternalError as err: print 'Error with key="%s" : %s' % (key, err.msg) # Native type string key = 'typicalDate' try: print ' %s: %s' % (key, codes_get(bufr, key)) except CodesInternalError as err: print 'Error with key="%s" : %s' % (key, err.msg) # -------------------------------- # get values for an array # -------------------------------- # Native type integer key = 'bufrdcExpandedDescriptors' # get size num = codes_get_size(bufr, key) print ' size of %s is: %s' % (key, num) # get values values = codes_get_array(bufr, key) for i in xrange(len(values)): print " %d %06d" % (i + 1, values[i]) # Native type float key = 'numericValues' # get size num = codes_get_size(bufr, key) print ' size of %s is: %s' % (key, num) # get values values = codes_get_array(bufr, key) for i in xrange(len(values)): print " %d %.10e" % (i + 1, values[i]) 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())
bufr_get_keys.c
/* * 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. */ /* * C Implementation: bufr_get_keys * * Description: how to read values of different type of keys from BUFR messages. * */ #include "eccodes.h" int main(int argc,char* argv[]) { FILE* in = NULL; /* message handle. Required in all the eccodes calls acting on a message.*/ codes_handle* h=NULL; long *descriptors=NULL; double *values = NULL; char* typicalDate= NULL; long longVal; double doubleVal; size_t values_len=0, desc_len=0, len=0; int i, err=0; int cnt=0; const char* infile = "../../data/bufr/syno_multi.bufr"; in=fopen(infile,"r"); if (!in) { printf("ERROR: unable to open file %s\n", infile); return 1; } /* loop over the messages in the bufr file */ while ((h = codes_handle_new_from_file(NULL, in, PRODUCT_BUFR, &err)) != NULL || err != CODES_SUCCESS) { if (h == NULL) { printf("Error: unable to create handle for message %d\n",cnt); cnt++; continue; } printf("message: %d\n",cnt); /* we need to instruct ecCodes to expand the descriptors i.e. unpack the data values */ CODES_CHECK(codes_set_long(h, "unpack", 1),0); /* read and print some data values */ /* long value */ CODES_CHECK(codes_get_long(h, "blockNumber", &longVal),0); printf(" blockNumber: %ld\n", longVal); /* long value */ CODES_CHECK(codes_get_long(h, "stationNumber", &longVal),0); printf(" stationNumber: %ld\n", longVal); /* double value */ CODES_CHECK(codes_get_double(h, "airTemperatureAt2M", &doubleVal),0); printf(" airTemperatureAt2M: %f\n", doubleVal); /* ---- string value -----------------*/ /* get the size and allocate memory*/ CODES_CHECK(codes_get_length(h, "typicalDate", &len), 0); typicalDate = (char*)malloc(len*sizeof(char)); /* get the values*/ codes_get_string(h, "typicalDate", typicalDate, &len); printf(" typicalDate: %s\n", typicalDate); /* ---- array of long ----------------*/ /* get the size and allocate memory*/ CODES_CHECK(codes_get_size(h, "bufrdcExpandedDescriptors", &desc_len),0); descriptors = (long*)malloc(desc_len*sizeof(long)); /* get the values */ CODES_CHECK(codes_get_long_array(h, "bufrdcExpandedDescriptors", descriptors, &desc_len),0); printf(" bufrdcExpandedDescriptors:\n"); for(i = 0; i < desc_len; i++) { printf(" %ld\n",descriptors[i]); } /* ---- array of double ---------------*/ /* get the size and allocate memory*/ CODES_CHECK(codes_get_size(h, "numericValues", &values_len),0); values = (double*)malloc(values_len*sizeof(double)); /* get the values*/ CODES_CHECK(codes_get_double_array(h, "numericValues", values, &values_len),0); printf(" numericValues:\n"); for(i = 0; i < values_len; i++) { printf(" %.10e\n",values[i]); } /* free allocated arrays */ free(descriptors); free(values); free(typicalDate); /* delete handle */ codes_handle_delete(h); cnt++; } fclose(in); return 0; }