mirror of https://github.com/ecmwf/eccodes.git
84 lines
2.4 KiB
C
84 lines
2.4 KiB
C
/*
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* Copyright 2005-2017 ECMWF.
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*
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* This software is licensed under the terms of the Apache Licence Version 2.0
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* which can be obtained at http://www.apache.org/licenses/LICENSE-2.0.
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*
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* In applying this licence, ECMWF does not waive the privileges and immunities granted to it by
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* virtue of its status as an intergovernmental organisation nor does it submit to any jurisdiction.
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*/
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/*
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* C Implementation: grib_get_data
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*
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* Description: how to get lat/lon/values from a GRIB message
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*
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*/
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#include <stdio.h>
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#include <stdlib.h>
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#include "eccodes.h"
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int main (int argc, char **argv)
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{
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int err = 0;
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size_t i = 0;
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FILE *in = NULL;
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const char *filename = "../../data/reduced_latlon_surface.grib1";
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codes_handle *h = NULL;
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long numberOfPoints = 0;
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const double missing = 9999.0;
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double *lats, *lons, *values; /* arrays */
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in = fopen (filename, "r");
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if (!in) {
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printf ("ERROR: unable to open input file %s\n", filename);
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return 1;
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}
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/* create new handle from a message in a file */
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h = codes_handle_new_from_file (0, in, PRODUCT_GRIB, &err);
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if (h == NULL) {
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printf ("Error: unable to create handle from file %s\n", filename);
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return 1;
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}
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CODES_CHECK (codes_get_long (h, "numberOfPoints", &numberOfPoints), 0);
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CODES_CHECK (codes_set_double (h, "missingValue", missing), 0);
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lats = (double *) malloc (numberOfPoints * sizeof (double));
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if (!lats) {
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printf ("unable to allocate %ld bytes\n", (long) (numberOfPoints * sizeof (double)));
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return 1;
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}
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lons = (double *) malloc (numberOfPoints * sizeof (double));
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if (!lons) {
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printf ("unable to allocate %ld bytes\n", (long) (numberOfPoints * sizeof (double)));
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free (lats);
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return 1;
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}
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values = (double *) malloc (numberOfPoints * sizeof (double));
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if (!values) {
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printf ("unable to allocate %ld bytes\n", (long) (numberOfPoints * sizeof (double)));
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free (lats);
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free (lons);
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return 1;
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}
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CODES_CHECK (codes_grib_get_data (h, lats, lons, values), 0);
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for (i = 0; i < numberOfPoints; ++i) {
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if (values[i] != missing) {
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printf ("%f %f %f\n", lats[i], lons[i], values[i]);
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}
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}
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free (lats);
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free (lons);
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free (values);
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codes_handle_delete (h);
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fclose (in);
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return 0;
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}
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