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/*
 * Copyright 2005-2015 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: grib_get_keys
 *
 * Description: how to get values using keys from GRIB messages
 *
 */
#include <stdio.h>
#include <stdlib.h>
#include <assert.h>
#include "eccodes.h"

int main(int argc, char** argv)
{
    int err = 0;
    double *values = NULL;
    size_t values_len= 0;
    size_t i = 0, len = 0;

    double latitudeOfFirstGridPointInDegrees;
    double longitudeOfFirstGridPointInDegrees;
    double latitudeOfLastGridPointInDegrees;
    double longitudeOfLastGridPointInDegrees;

    double jDirectionIncrementInDegrees;
    double iDirectionIncrementInDegrees;

    long numberOfPointsAlongAParallel;
    long numberOfPointsAlongAMeridian;

    double average = 0;
    char* packingType = NULL;

    FILE* in = NULL;
    const char* filename = "../../data/regular_latlon_surface.grib1";
    codes_handle *h = NULL;

    in = fopen(filename,"r");
    if(!in (h == NULL) {
        printf("ERRORError: unable to opencreate handle from file %s\n",filename);
        return 1;
    }
    fclose(in);

    /* createStore newthe handlefilename fromin the first message in the filekey "file" for this handle */
    hlen = strlen(filename);
    CODES_CHECK(codes_handle_new_from_file(0, in, PRODUCT_GRIB, &err);set_string(h, "file", filename, &len), 0);

    if/* (hget ==as NULL) {a long*/
    CODES_CHECK(codes_get_long(h,"Ni",&numberOfPointsAlongAParallel),0);
      printf("Error: unable to create handle from file %snumberOfPointsAlongAParallel=%ld\n",filenamenumberOfPointsAlongAParallel);

    /* get as  return 1;a long*/
    }CODES_CHECK(codes_get_long(h,"Nj",&numberOfPointsAlongAMeridian),0);
    fclose(in printf("numberOfPointsAlongAMeridian=%ld\n",numberOfPointsAlongAMeridian);

    /* get Storeas the filename in the key "file" for this handle */
    len = strlen(filename);a double*/
    CODES_CHECK(codes_get_double(h,"latitudeOfFirstGridPointInDegrees",&latitudeOfFirstGridPointInDegrees),0);
    printf("latitudeOfFirstGridPointInDegrees=%g\n",latitudeOfFirstGridPointInDegrees);

    /* get as a double*/
    CODES_CHECK(codes_setget_stringdouble(h, "filelongitudeOfFirstGridPointInDegrees", filename, &lenlongitudeOfFirstGridPointInDegrees), 00);
    printf("longitudeOfFirstGridPointInDegrees=%g\n",longitudeOfFirstGridPointInDegrees);

    /* get as a longdouble*/
    CODES_CHECK(codes_get_longdouble(h,"NilatitudeOfLastGridPointInDegrees",&numberOfPointsAlongAParallellatitudeOfLastGridPointInDegrees),0);
    printf("numberOfPointsAlongAParallellatitudeOfLastGridPointInDegrees=%ld%g\n",numberOfPointsAlongAParallellatitudeOfLastGridPointInDegrees);

    /* get as a longdouble*/
    CODES_CHECK(codes_get_longdouble(h,"NjlongitudeOfLastGridPointInDegrees",&numberOfPointsAlongAMeridianlongitudeOfLastGridPointInDegrees),0);
    printf("numberOfPointsAlongAMeridianlongitudeOfLastGridPointInDegrees=%ld%g\n",numberOfPointsAlongAMeridianlongitudeOfLastGridPointInDegrees);

    /* get as a double*/
    CODES_CHECK(codes_get_double(h,"latitudeOfFirstGridPointInDegreesjDirectionIncrementInDegrees",&latitudeOfFirstGridPointInDegreesjDirectionIncrementInDegrees),0);
    printf("latitudeOfFirstGridPointInDegreesjDirectionIncrementInDegrees=%g\n",latitudeOfFirstGridPointInDegreesjDirectionIncrementInDegrees);

    /* get as a double*/
    CODES_CHECK(codes_get_double(h,"longitudeOfFirstGridPointInDegreesiDirectionIncrementInDegrees",&longitudeOfFirstGridPointInDegreesiDirectionIncrementInDegrees),0);
    printf("longitudeOfFirstGridPointInDegreesiDirectionIncrementInDegrees=%g\n",longitudeOfFirstGridPointInDegreesiDirectionIncrementInDegrees);

    /* get as astring double*/
    CODES_CHECK((codes_get_length(h, "packingType", &len), 0);
    packingType = (char*)malloc(len*sizeof(char));
    codes_get_doublestring(h, "latitudeOfLastGridPointInDegreespackingType", packingType, &latitudeOfLastGridPointInDegreeslen),0);
    printf("latitudeOfLastGridPointInDegreespackingType=%g%s\n",latitudeOfLastGridPointInDegrees packingType);
    free(packingType);

    /* get as a double the size of the values array*/
    CODES_CHECK(codes_get_doublesize(h,"longitudeOfLastGridPointInDegreesvalues",&longitudeOfLastGridPointInDegreesvalues_len),0);

    printf("longitudeOfLastGridPointInDegrees=%g\n",longitudeOfLastGridPointInDegreesvalues = (double*)malloc(values_len*sizeof(double));

    /* get asdata a doublevalues*/
    CODES_CHECK(codes_get_double_array(h,"jDirectionIncrementInDegreesvalues",values,&jDirectionIncrementInDegreesvalues_len),0);

    average = 0;
    printffor("jDirectionIncrementInDegrees=%g\n",jDirectionIncrementInDegrees);

    /* get as a double*/
    CODES_CHECK(codes_get_double(h,"iDirectionIncrementInDegrees",&iDirectionIncrementInDegrees),0);
    printf("iDirectionIncrementInDegrees=%g\n",iDirectionIncrementInDegrees)i = 0; i < values_len; i++)
        average += values[i];

    average /=(double)values_len;

    /* get as string */free(values);

    CODES_CHECK(codes_get_length(h, "packingType", &len), 0);printf("There are %d values, average is %g\n",(int)values_len,average);

    packingType = (char*)malloc(len*sizeof(char));{
    codes_get_string(h, "packingType", packingType, &len);
  int eq printf("packingType=%s\n", packingType) 0;
    free(packingType);

    /* Now getretrieve the sizevalue of the values array*/
    CODES_CHECK(codes_get_size(h,"values",&values_len),0);

key "file" */
    values = (double*)malloc(values_len*sizeof(double));

  char  /* get data values*/
file[256]={0,};
        CODES_CHECK(codes_get_double_arraylength(h, "valuesfile",values, &values_len),0);

    average = 00);
    for(i = 0; i < values_len; i++)assert(len == 1+strlen(filename));
        average += values[i];

 codes_get_string(h, "file", file, &len);
        averageeq /=(double)values_len strcmp(file, filename);

     free(values);

   if printf("There are %d values, average is %g\n",(int)values_len,average);

(eq != 0) assert(!"file and filename not equal");
    {}

        int eq = 0;{
        /* Now retrieve the valueExample of the key "file"getting bytes */
        const char file[256]={0,}* name = "reservedNeedNotBePresent";
        CODES_CHECK(codes_get_length(h, "file", &len),0)unsigned char* byte_val = NULL ;
        assert(len == 1+strlen(filename))size_t keySize = 0;
        CODES_CHECK(codes_get_stringsize(h, "file"name, file&keySize), &len0);
        eqbyte_val = strcmp(file, filenameunsigned char*)malloc(keySize*sizeof(char));
        assert( eq == 0 GRIB_CHECK(codes_get_bytes(h, name, byte_val, &keySize), name);
    }

    codes_handle_delete(h);

    return 0;
}