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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_set_bitmap
*
* Description: how to set a bitmap in a GRIB message
*
*/
#include <stdio.h>
#include <stdlib.h>
#include <assert.h>
#include "eccodes.h"
int main(int argc, char** argv)
{
int err = 0, i = 0, NUM_MISSING = 10;
FILE* in = NULL;
const char* infile = "../../data/regular_latlon_surface.grib1";
FILE* out = NULL;
const char* outfile = "out.set_bitmap_c.grib";
codes_handle* h = NULL;
const void* buffer = NULL;
size_t values_len = 0, size = 0;
long num_of_data_points = 0, num_of_coded_values = 0, num_of_missing = 0;
double* values;
const double missing = 1.0e36;
in = fopen(infile, "rb");
if (!in) {
fprintf(stderr, "Error: unable to open input file %s\n", infile);
return 1;
}
out = fopen(outfile, "wb");
if (!out) {
fprintf(stderr, "Error: unable to open output file %s\n", outfile);
fclose(in);
return 1;
}
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", infile);
fclose(out);
return 1;
}
CODES_CHECK(codes_set_double(h, "missingValue", missing), 0);
/* get the size of the values array*/
CODES_CHECK(codes_get_size(h, "values", &values_len), 0);
values = (double*)malloc(values_len * sizeof(double));
/* get data values*/
CODES_CHECK(codes_get_double_array(h, "values", values, &values_len), 0);
/* enable bitmap */
CODES_CHECK(codes_set_long(h, "bitmapPresent", 1), 0);
/* set some values to be missing */
for (i = 0; i < NUM_MISSING; i++) {
values[i] = missing;
}
/* set the values (the bitmap will be automatically built) */
CODES_CHECK(codes_set_double_array(h, "values", values, values_len), 0);
/* sanity checks */
CODES_CHECK(codes_get_long(h, "numberOfDataPoints", &num_of_data_points), 0);
CODES_CHECK(codes_get_long(h, "numberOfCodedValues", &num_of_coded_values), 0);
CODES_CHECK(codes_get_long(h, "numberOfMissing", &num_of_missing), 0);
assert(num_of_data_points == values_len);
assert(num_of_coded_values == num_of_data_points - num_of_missing);
assert(num_of_missing == NUM_MISSING);
/* get the coded message in a buffer */
CODES_CHECK(codes_get_message(h, &buffer, &size), 0);
/* write the buffer in a file*/
if (fwrite(buffer, 1, size, out) != size) {
perror(outfile);
exit(1);
}
codes_handle_delete(h);
free(values);
fclose(in);
fclose(out);
return 0;
}
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