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/*
* (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.
*/
/*
* C Implementation: grib_get_data
*
* Description: how to get lat/lon/values from a GRIB message
*
*/
#include <stdio.h>
#include <stdlib.h>
#include "eccodes.h"
int main(int argc, char** argv)
{
int err = 0;
size_t i = 0;
FILE* in = NULL;
const char* filename = "../../data/reduced_latlon_surface.grib1";
codes_handle* h = NULL;
long numberOfPoints = 0;
const double missing = 9999.0;
double *lats, *lons, *values; /* arrays */
in = fopen(filename, "rb");
if (!in) {
fprintf(stderr, "Error: unable to open input file %s\n", filename);
return 1;
}
/* create new handle from a message in a file */
h = codes_handle_new_from_file(0, in, PRODUCT_GRIB, &err);
if (h == NULL) {
fprintf(stderr, "Error: unable to create handle from file %s\n", filename);
return 1;
}
CODES_CHECK(codes_get_long(h, "numberOfPoints", &numberOfPoints), 0);
CODES_CHECK(codes_set_double(h, "missingValue", missing), 0);
lats = (double*)malloc(numberOfPoints * sizeof(double));
if (!lats) {
fprintf(stderr, "Error: unable to allocate %ld bytes\n", (long)(numberOfPoints * sizeof(double)));
return 1;
}
lons = (double*)malloc(numberOfPoints * sizeof(double));
if (!lons) {
fprintf(stderr, "Error: unable to allocate %ld bytes\n", (long)(numberOfPoints * sizeof(double)));
free(lats);
return 1;
}
values = (double*)malloc(numberOfPoints * sizeof(double));
if (!values) {
fprintf(stderr, "Error: unable to allocate %ld bytes\n", (long)(numberOfPoints * sizeof(double)));
free(lats);
free(lons);
return 1;
}
CODES_CHECK(codes_grib_get_data(h, lats, lons, values), 0);
for (i = 0; i < numberOfPoints; ++i) {
if (values[i] != missing) {
printf("%f %f %f\n", lats[i], lons[i], values[i]);
}
}
free(lats);
free(lons);
free(values);
codes_handle_delete(h);
fclose(in);
return 0;
}
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