eccodes/examples/examples.dev/create_grib.c

123 lines
2.7 KiB
C

/*
* C Implementation: create_grib
*
* Description:
*
*
* Author: Enrico Fucile <enrico.fucile@ecmwf.int>, (C) 2006
*
* Copyright: See COPYING file that comes with this distribution
*
*/
#include <stdio.h>
#include "grib_api_internal.h"
int main(int argc, char *argv[])
{
FILE* of=NULL;
const void* buffer=NULL;
int ret=0;
size_t size;
double* values=NULL;
long numberOfPointsAlongAParallel=0;
long numberOfPointsAlongAMeridian=0;
long numberOfPoints = 0,i = 0,j = 0,k = 0;
grib_context* c=NULL;
grib_handle* h=NULL;
char* outfilename="out.grib";
long missing=9999;
#if 0
FILE *f=NULL;
char* infilename="../data/sample_grib.txt";
f = fopen(infilename,"r");
if(!f) {
perror(argv[i]);
exit(1);
}
h=grib_handle_new_from_text_file(c,f);
fclose(f);
#endif
#if 0
FILE *f=NULL;
char* infilename="../data/sample_grib.txt";
f = fopen(infilename,"r");
if(!f) {
perror(argv[i]);
exit(1);
}
h=grib_handle_new(c);
GRIB_CHECK(grib_load_from_text_file(h,f),0);
fclose(f);
#endif
#if 1
h=grib_handle_new(c);
GRIB_CHECK(grib_set_type(h,"grib1"),0);
GRIB_CHECK(grib_set_type(h,"ecmwf"),0);
GRIB_CHECK(grib_set_type(h,"geopotential"),0);
#endif
GRIB_CHECK(grib_set_long(h,"generatingProcessIdentifier",127),0);
GRIB_CHECK(grib_set_double(h,"latitudeOfFirstGridPointInDegrees",10),0);
GRIB_CHECK(grib_set_double(h,"longitudeOfFirstGridPointInDegrees",-10),0);
GRIB_CHECK(grib_set_double(h,"latitudeOfLastGridPointInDegrees",-10),0);
GRIB_CHECK(grib_set_double(h,"longitudeOfLastGridPointInDegrees",10),0);
GRIB_CHECK(grib_set_double(h,"jDirectionIncrementInDegrees",0.5),0);
GRIB_CHECK(grib_set_double(h,"iDirectionIncrementInDegrees",0.5),0);
GRIB_CHECK(grib_set_long(h,"section3Present",1),0);
GRIB_CHECK(grib_set_long(h,"missingValue",missing),0);
GRIB_CHECK(grib_get_long( h,"numberOfPointsAlongAParallel",&numberOfPointsAlongAParallel),0);
GRIB_CHECK(grib_get_long( h,"numberOfPointsAlongAMeridian",&numberOfPointsAlongAMeridian),0);
numberOfPoints=numberOfPointsAlongAMeridian*numberOfPointsAlongAParallel;
values=(double*)malloc(numberOfPoints*sizeof(double));
for (j=0;j<numberOfPointsAlongAMeridian;j++) {
for (i=0;i<numberOfPointsAlongAParallel;i++) {
k=i+numberOfPointsAlongAParallel*j;
if (i==j) values[k]=missing;
else values[k]=50;
}
}
grib_set_data_array( h,values,numberOfPoints);
if (h) {
grib_dump_content(h,stdout,"debug",0,NULL);
} else {
printf("Error: unable to create grib_handle\n");
}
of = fopen(outfilename,"w");
if(!of) {
perror(outfilename);
exit(1);
}
grib_get_message(h,&buffer,&size);
if(fwrite(buffer,1,size,of) != size) {
perror(outfilename);
exit(1);
}
fclose(of);
return ret;
}