eccodes/examples/C/grib_precipitation.c

74 lines
1.8 KiB
C

/*
* (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_precipitation
*
* Description: convert fields accumulated from 0 step in
* fields accumulated in the interval between
* a field and another. In the input file the fields
* must be in ascending order in the step.
* step must be the most external loop (slower varying index)
*
*
*
*/
#include <stdio.h>
#include <stdlib.h>
#include "eccodes.h"
void usage(const char* prog)
{
printf("usage: %s filename\n", prog);
exit(1);
}
int main(int argc, char** argv)
{
int err = 0, i;
double* values = NULL;
size_t values_len = 0;
FILE* in = NULL;
char* filename;
codes_handle* h = NULL;
if (argc < 2) usage(argv[0]);
filename = argv[1];
in = fopen(filename, "rb");
if (!in) {
fprintf(stderr, "ERROR: unable to open file %s\n", filename);
return 1;
}
/* create new handle from a message in a file*/
while ((h = codes_handle_new_from_file(0, in, &err)) != NULL) {
/* get the size of the values array*/
CODES_CHECK(codes_get_size(h, "values", &values_len), 0);
values = malloc(values_len * sizeof(double));
/* get data values*/
CODES_CHECK(codes_get_double_array(h, "values", values, &values_len), 0);
for (i = 0; i < values_len; i++)
printf("%d %.10e\n", i + 1, values[i]);
free(values);
codes_handle_delete(h);
}
fclose(in);
return 0;
}