eccodes/tests/grib_sh_imag.cc

/*
 * (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.
 */

#include "grib_api_internal.h"

/*
 * Check that first coefficient have an imaginary part equal to zero.
 * philippe.marguinaud@meteo.fr, 2016/02
 */

#include "grib_sh_values.h" /* array 'values' defined here*/

#define ILCHAM 992
#define MTRONC 30
#define STRONC 10

int main(int argc, char* argv[])
{
    size_t len;
    grib_handle* h;
    double zval[ILCHAM];
    int m, n, k;
    const char* outfile;

    ECCODES_ASSERT(argc == 2);
    outfile = argv[1];

    GRIB_CHECK(((h = grib_handle_new_from_samples(NULL, "sh_ml_grib2")) == NULL), 0);

    /* Meteo-France settings */
    GRIB_CHECK(grib_set_long(h, "centre", 85), 0);
    len = strlen("stretched_rotated_sh");
    GRIB_CHECK(grib_set_string(h, "gridType", "stretched_rotated_sh", &len), 0);
    GRIB_CHECK(grib_set_long(h, "pentagonalResolutionParameterJ", MTRONC), 0);
    GRIB_CHECK(grib_set_long(h, "pentagonalResolutionParameterK", MTRONC), 0);
    GRIB_CHECK(grib_set_long(h, "pentagonalResolutionParameterM", MTRONC), 0);

    GRIB_CHECK(grib_set_double(h, "stretchingFactor", 2.40000000000000), 0);
    GRIB_CHECK(grib_set_double(h, "latitudeOfStretchingPoleInDegrees", 46.4688478326275), 0);
    GRIB_CHECK(grib_set_double(h, "longitudeOfStretchingPoleInDegrees", 2.57831007808864), 0);

    GRIB_CHECK(grib_set_long(h, "bitsPerValue", 16), 0);
    len = strlen("spectral_complex");
    GRIB_CHECK(grib_set_string(h, "packingType", "spectral_complex", &len), 0);

    GRIB_CHECK(grib_set_long(h, "subSetJ", STRONC), 0);
    GRIB_CHECK(grib_set_long(h, "subSetK", STRONC), 0);
    GRIB_CHECK(grib_set_long(h, "subSetM", STRONC), 0);
    GRIB_CHECK(grib_set_long(h, "unpackedSubsetPrecision", 1), 0);

    GRIB_CHECK(grib_set_double_array(h, "values", values, ILCHAM), 0);
    len = ILCHAM;
    GRIB_CHECK(grib_get_double_array(h, "values", zval, &len), 0);

    for (m = 0, k = 0; m < MTRONC + 1; m++) {
        for (n = MTRONC - m; n < MTRONC + 1; k++, n++) {
            /* Check that imaginary part of first coefficients is zero */
            if ((m == 0) && (zval[2 * k + 1] != 0.)) {
                printf("Imaginary part of coefficient (m=%d,n=%d) should be zero\n", m, n);
                return 1;
            }
        }
    }

    GRIB_CHECK(grib_write_message(h, outfile, "w"), 0);
    GRIB_CHECK(grib_handle_delete(h), 0);
    printf("ALL OK\n");

    return 0;
}