static void compute_enu_directions(oskar_Mem* x, oskar_Mem* y, oskar_Mem* z,
        int np, const oskar_Mem* l, const oskar_Mem* m, const oskar_Mem* n,
        const oskar_Station* station, double GAST, int* status)
{
    double ha0, dec0;
    oskar_mem_ensure(x, np, status);
    oskar_mem_ensure(y, np, status);
    oskar_mem_ensure(z, np, status);
    if (*status) return;

    /* Obtain ra0, dec0 of phase centre */
    const double lat  = oskar_station_lat_rad(station);
    const int pointing_coord_type = oskar_station_beam_coord_type(station);
    if (pointing_coord_type == OSKAR_SPHERICAL_TYPE_EQUATORIAL)
    {
        const double ra0 = oskar_station_beam_lon_rad(station);
        ha0  = (GAST + oskar_station_lon_rad(station)) - ra0;
        dec0 = oskar_station_beam_lat_rad(station);
    }
    else if (pointing_coord_type == OSKAR_SPHERICAL_TYPE_AZEL)
    {
        /* TODO convert from az0, el0 to ha0, dec0 */
        ha0 = 0.0;
        dec0 = 0.0;
        *status = OSKAR_ERR_FUNCTION_NOT_AVAILABLE;
        return;
    }
    else
    {
        *status = OSKAR_ERR_SETTINGS_TELESCOPE;
        return;
    }
    oskar_convert_relative_directions_to_enu_directions(
            0, 0, 0, np, l, m, n, ha0, dec0, lat, 0, x, y, z, status);
}
Esempio n. 2
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static void compute_relative_directions(oskar_Mem* l, oskar_Mem* m,
        oskar_Mem* n, int np, const oskar_Mem* x, const oskar_Mem* y,
        const oskar_Mem* z, const oskar_Station* station, double GAST,
        int* status)
{
    double ha0, dec0, lat;
    int pointing_coord_type;

    if (*status) return;

    /* Resize work arrays if needed */
    if ((int)oskar_mem_length(l) < np) oskar_mem_realloc(l, np, status);
    if ((int)oskar_mem_length(m) < np) oskar_mem_realloc(m, np, status);
    if ((int)oskar_mem_length(n) < np) oskar_mem_realloc(n, np, status);
    if (*status) return;

    /* Obtain ra0, dec0 of phase centre */
    lat  = oskar_station_lat_rad(station);
    pointing_coord_type = oskar_station_beam_coord_type(station);
    if (pointing_coord_type == OSKAR_SPHERICAL_TYPE_EQUATORIAL)
    {
        double ra0;
        ra0  = oskar_station_beam_lon_rad(station);
        ha0  = (GAST + oskar_station_lon_rad(station)) - ra0;
        dec0 = oskar_station_beam_lat_rad(station);
    }
    else if (pointing_coord_type == OSKAR_SPHERICAL_TYPE_AZEL)
    {
        /* TODO convert from az0, el0 to ha0, dec0 */
        ha0 = 0.0;
        dec0 = 0.0;
        *status = OSKAR_FAIL;
        return;
    }
    else
    {
        *status = OSKAR_ERR_SETTINGS_TELESCOPE;
        return;
    }

    /* Convert from ENU to phase-centre-relative directions. */
    oskar_convert_enu_directions_to_relative_directions(
            l, m, n, np, x, y, z, ha0, dec0, lat, status);
}
Esempio n. 3
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static void set_child_station_locations(oskar_Station* s,
        const oskar_Station* parent)
{
    if (parent)
    {
        oskar_station_set_position(s,
                oskar_station_lon_rad(parent),
                oskar_station_lat_rad(parent),
                oskar_station_alt_metres(parent));
    }

    /* Recursively set data for child stations. */
    if (oskar_station_has_child(s))
    {
        int i, num_elements;
        num_elements = oskar_station_num_elements(s);
        for (i = 0; i < num_elements; ++i)
            set_child_station_locations(oskar_station_child(s, i), s);
    }
}
Esempio n. 4
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static void evaluate_station_ECEF_coords(
        double* station_x, double* station_y, double* station_z,
        int stationID, const oskar_Telescope* telescope)
{
    double st_x, st_y, st_z;
    double lon, lat, alt;
    const oskar_Station* station;
    const void *x_, *y_, *z_;

    x_ = oskar_mem_void_const(
            oskar_telescope_station_true_x_offset_ecef_metres_const(telescope));
    y_ = oskar_mem_void_const(
            oskar_telescope_station_true_y_offset_ecef_metres_const(telescope));
    z_ = oskar_mem_void_const(
            oskar_telescope_station_true_z_offset_ecef_metres_const(telescope));
    station = oskar_telescope_station_const(telescope, stationID);
    lon = oskar_station_lon_rad(station);
    lat = oskar_station_lat_rad(station);
    alt = oskar_station_alt_metres(station);

    if (oskar_mem_type(
            oskar_telescope_station_true_x_offset_ecef_metres_const(telescope)) ==
            OSKAR_DOUBLE)
    {
        st_x = ((const double*)x_)[stationID];
        st_y = ((const double*)y_)[stationID];
        st_z = ((const double*)z_)[stationID];
    }
    else
    {
        st_x = (double)((const float*)x_)[stationID];
        st_y = (double)((const float*)y_)[stationID];
        st_z = (double)((const float*)z_)[stationID];
    }

    oskar_convert_offset_ecef_to_ecef(1, &st_x, &st_y, &st_z, lon, lat, alt,
            station_x, station_y, station_z);
}
Esempio n. 5
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void oskar_evaluate_station_beam(oskar_Mem* beam_pattern, int num_points,
        int coord_type, oskar_Mem* x, oskar_Mem* y, oskar_Mem* z,
        double norm_ra_rad, double norm_dec_rad, const oskar_Station* station,
        oskar_StationWork* work, int time_index, double frequency_hz,
        double GAST, int* status)
{
    int normalise_final_beam;
    oskar_Mem* out;

    /* Check if safe to proceed. */
    if (*status) return;

    /* Set default output beam array. */
    out = beam_pattern;

    /* Check that the arrays have enough space to add an extra source at the
     * end (for normalisation). We don't want to reallocate here, since that
     * will be slow to do each time: must simply ensure that we pass input
     * arrays that are large enough.
     * The normalisation doesn't need to happen if the station has an
     * isotropic beam. */
    normalise_final_beam = oskar_station_normalise_final_beam(station) &&
            (oskar_station_type(station) != OSKAR_STATION_TYPE_ISOTROPIC);
    if (normalise_final_beam)
    {
        double c_x = 0.0, c_y = 0.0, c_z = 1.0;

        /* Increment number of points. */
        num_points++;

        /* Check the input arrays are big enough to hold the new source. */
        if ((int)oskar_mem_length(x) < num_points ||
                (int)oskar_mem_length(y) < num_points ||
                (int)oskar_mem_length(z) < num_points)
        {
            *status = OSKAR_ERR_DIMENSION_MISMATCH;
            return;
        }

        /* Set output beam array to work buffer. */
        out = oskar_station_work_normalised_beam(work, beam_pattern, status);

        /* Get the beam direction in the appropriate coordinate system. */
        /* (Direction cosines are already set to the interferometer phase
         * centre for relative directions.) */
        if (coord_type == OSKAR_ENU_DIRECTIONS)
        {
            double t_x, t_y, t_z, ha0;
            ha0 = (GAST + oskar_station_lon_rad(station)) - norm_ra_rad;
            oskar_convert_relative_directions_to_enu_directions_d(
                    &t_x, &t_y, &t_z, 1, &c_x, &c_y, &c_z, ha0, norm_dec_rad,
                    oskar_station_lat_rad(station));
            c_x = t_x;
            c_y = t_y;
            c_z = t_z;
        }

        /* Add the extra normalisation source to the end of the arrays. */
        oskar_mem_set_element_real(x, num_points-1, c_x, status);
        oskar_mem_set_element_real(y, num_points-1, c_y, status);
        oskar_mem_set_element_real(z, num_points-1, c_z, status);
    }

    /* Evaluate the station beam for the given directions. */
    if (coord_type == OSKAR_ENU_DIRECTIONS)
    {
        evaluate_station_beam_enu_directions(out, num_points, x, y, z,
                station, work, time_index, frequency_hz, GAST, status);
    }
    else if (coord_type == OSKAR_RELATIVE_DIRECTIONS)
    {
        evaluate_station_beam_relative_directions(out, num_points, x, y, z,
                station, work, time_index, frequency_hz, GAST, status);
    }
    else
    {
        *status = OSKAR_ERR_INVALID_ARGUMENT;
    }

    /* Scale beam pattern by value of the last source if required. */
    if (normalise_final_beam)
    {
        double amp = 0.0;

        /* Get the last element of the vector and convert to amplitude. */
        if (oskar_mem_is_matrix(out))
        {
            double4c val;
            val = oskar_mem_get_element_matrix(out, num_points-1, status);

            /*
             * Scale by square root of "Stokes I" autocorrelation:
             * sqrt(0.5 * [sum of resultant diagonal]).
             *
             * We have
             * [ Xa  Xb ] [ Xa*  Xc* ] = [ Xa Xa* + Xb Xb*    (don't care)   ]
             * [ Xc  Xd ] [ Xb*  Xd* ]   [  (don't care)     Xc Xc* + Xd Xd* ]
             *
             * Stokes I is completely real, so need only evaluate the real
             * part of all the multiplies. Because of the conjugate terms,
             * these become re*re + im*im.
             *
             * Need the square root because we only want the normalised value
             * for the beam itself (in isolation), not its actual
             * autocorrelation!
             */
            amp = val.a.x * val.a.x + val.a.y * val.a.y +
                    val.b.x * val.b.x + val.b.y * val.b.y +
                    val.c.x * val.c.x + val.c.y * val.c.y +
                    val.d.x * val.d.x + val.d.y * val.d.y;
            amp = sqrt(0.5 * amp);
        }
        else
        {
            double2 val;
            val = oskar_mem_get_element_complex(out, num_points-1, status);

            /* Scale by voltage. */
            amp = sqrt(val.x * val.x + val.y * val.y);
        }

        /* Scale beam array by normalisation value. */
        oskar_mem_scale_real(out, 1.0/amp, status);

        /* Copy output beam data. */
        oskar_mem_copy_contents(beam_pattern, out, 0, 0, num_points-1, status);
    }
}
Esempio n. 6
0
void oskar_evaluate_jones_Z(oskar_Jones* Z, const oskar_Sky* sky,
        const oskar_Telescope* telescope,
        const oskar_SettingsIonosphere* settings, double gast,
        double frequency_hz, oskar_WorkJonesZ* work, int* status)
{
    int i, num_sources, num_stations;
    /* Station position in ECEF frame */
    double station_x, station_y, station_z, wavelength;
    oskar_Mem *Z_station;
    int type;
    oskar_Sky* sky_cpu; /* Copy of the sky model on the CPU */

    /* Check if safe to proceed. */
    if (*status) return;

    /* Check data types. */
    type = oskar_sky_precision(sky);
    if (oskar_telescope_precision(telescope) != type ||
            oskar_jones_type(Z) != (type | OSKAR_COMPLEX) ||
            oskar_work_jones_z_type(work) != type)
    {
        *status = OSKAR_ERR_BAD_DATA_TYPE;
        return;
    }

    /* For now, this function requires data is on the CPU .. check this. */

    /* Resize the work array (if needed) */
    num_stations = oskar_telescope_num_stations(telescope);
    num_sources = oskar_sky_num_sources(sky);
    oskar_work_jones_z_resize(work, num_sources, status);

    /* Copy the sky model to the CPU. */
    sky_cpu = oskar_sky_create_copy(sky, OSKAR_CPU, status);

    Z_station = oskar_mem_create_alias(0, 0, 0, status);
    wavelength = 299792458.0 / frequency_hz;

    /* Evaluate the ionospheric phase screen for each station at each
     * source pierce point. */
    for (i = 0; i < num_stations; ++i)
    {
        double last, lon, lat;
        const oskar_Station* station;
        station = oskar_telescope_station_const(telescope, i);
        lon = oskar_station_lon_rad(station);
        lat = oskar_station_lat_rad(station);
        last = gast + lon;

        /* Evaluate horizontal x,y,z source positions (for which to evaluate
         * pierce points) */
        oskar_convert_relative_directions_to_enu_directions(
                work->hor_x, work->hor_y, work->hor_z, num_sources,
                oskar_sky_l_const(sky_cpu), oskar_sky_m_const(sky_cpu),
                oskar_sky_n_const(sky_cpu), last - oskar_sky_reference_ra_rad(sky_cpu),
                oskar_sky_reference_dec_rad(sky_cpu), lat, status);

        /* Obtain station coordinates in the ECEF frame. */
        evaluate_station_ECEF_coords(&station_x, &station_y, &station_z, i,
                telescope);

        /* Obtain the pierce points. */
        /* FIXME(BM) this is current hard-coded to TID height screen 0
         * this fix is only needed to support multiple screen heights. */
        oskar_evaluate_pierce_points(work->pp_lon, work->pp_lat,
                work->pp_rel_path, station_x, station_y,
                station_z, settings->TID[0].height_km * 1000., num_sources,
                work->hor_x, work->hor_y, work->hor_z, status);

        /* Evaluate TEC values for the pierce points */
        oskar_evaluate_TEC(work, num_sources, settings, gast, status);

        /* Get a pointer to the Jones matrices for the station */
        oskar_jones_get_station_pointer(Z_station, Z, i, status);

        /* Populate the Jones matrix with ionospheric phase */
        evaluate_jones_Z_station(Z_station, wavelength,
                work->total_TEC, work->hor_z, settings->min_elevation,
                num_sources, status);
    }

    oskar_sky_free(sky_cpu, status);
    oskar_mem_free(Z_station, status);
}
int main(int argc, char** argv)
{
    int status = 0;
    oskar::OptionParser opt("oskar_evaulate_pierce_points",
            oskar_version_string());
    opt.add_required("settings file");
    if (!opt.check_options(argc, argv)) return EXIT_FAILURE;

    const char* settings_file = opt.get_arg();

    // Create the log.
    oskar_Log* log = oskar_log_create(OSKAR_LOG_MESSAGE, OSKAR_LOG_STATUS);
    oskar_log_message(log, 'M', 0, "Running binary %s", argv[0]);

    // Enum values used in writing time-freq data binary files
    enum OSKAR_TIME_FREQ_TAGS
    {
        TIME_IDX       = 0,
        FREQ_IDX       = 1,
        TIME_MJD_UTC   = 2,
        FREQ_HZ        = 3,
        NUM_FIELDS     = 4,
        NUM_FIELD_TAGS = 5,
        HEADER_OFFSET  = 10,
        DATA           = 0,
        DIMS           = 1,
        LABEL          = 2,
        UNITS          = 3,
        GRP            = OSKAR_TAG_GROUP_TIME_FREQ_DATA
    };

    oskar_Settings_old settings;
    oskar_settings_old_load(&settings, log, settings_file, &status);
    oskar_log_set_keep_file(log, settings.sim.keep_log_file);
    if (status) return status;

    oskar_Telescope* tel = oskar_settings_to_telescope(&settings, log, &status);
    oskar_Sky* sky = oskar_settings_to_sky(&settings, log, &status);

    // FIXME remove this restriction ... (see evaluate Z)
    if (settings.ionosphere.num_TID_screens != 1)
        return OSKAR_ERR_SETUP_FAIL;

    int type = settings.sim.double_precision ? OSKAR_DOUBLE : OSKAR_SINGLE;
    int loc = OSKAR_CPU;

    int num_sources = oskar_sky_num_sources(sky);
    oskar_Mem *hor_x, *hor_y, *hor_z;
    hor_x = oskar_mem_create(type, loc, num_sources, &status);
    hor_y = oskar_mem_create(type, loc, num_sources, &status);
    hor_z = oskar_mem_create(type, loc, num_sources, &status);

    oskar_Mem *pp_lon, *pp_lat, *pp_rel_path;
    int num_stations = oskar_telescope_num_stations(tel);

    int num_pp = num_stations * num_sources;
    pp_lon = oskar_mem_create(type, loc, num_pp, &status);
    pp_lat = oskar_mem_create(type, loc, num_pp, &status);
    pp_rel_path = oskar_mem_create(type, loc, num_pp, &status);

    // Pierce points for one station (non-owned oskar_Mem pointers)
    oskar_Mem *pp_st_lon, *pp_st_lat, *pp_st_rel_path;
    pp_st_lon = oskar_mem_create_alias(0, 0, 0, &status);
    pp_st_lat = oskar_mem_create_alias(0, 0, 0, &status);
    pp_st_rel_path = oskar_mem_create_alias(0, 0, 0, &status);

    int num_times = settings.obs.num_time_steps;
    double obs_start_mjd_utc = settings.obs.start_mjd_utc;
    double dt_dump = settings.obs.dt_dump_days;

    // Binary file meta-data
    std::string label1 = "pp_lon";
    std::string label2 = "pp_lat";
    std::string label3 = "pp_path";
    std::string units  = "radians";
    std::string units2 = "";
    oskar_Mem *dims = oskar_mem_create(OSKAR_INT, loc, 2, &status);
    /* FIXME is this the correct dimension order ?
     * FIXME get the MATLAB reader to respect dimension ordering */
    oskar_mem_int(dims, &status)[0] = num_sources;
    oskar_mem_int(dims, &status)[1] = num_stations;

    const char* filename = settings.ionosphere.pierce_points.filename;
    oskar_Binary* h = oskar_binary_create(filename, 'w', &status);

    double screen_height_m = settings.ionosphere.TID->height_km * 1000.0;

//    printf("Number of times    = %i\n", num_times);
//    printf("Number of stations = %i\n", num_stations);

    void *x_, *y_, *z_;
    x_ = oskar_mem_void(oskar_telescope_station_true_x_offset_ecef_metres(tel));
    y_ = oskar_mem_void(oskar_telescope_station_true_y_offset_ecef_metres(tel));
    z_ = oskar_mem_void(oskar_telescope_station_true_z_offset_ecef_metres(tel));

    for (int t = 0; t < num_times; ++t)
    {
        double t_dump = obs_start_mjd_utc + t * dt_dump; // MJD UTC
        double gast = oskar_convert_mjd_to_gast_fast(t_dump + dt_dump / 2.0);

        for (int i = 0; i < num_stations; ++i)
        {
            const oskar_Station* station =
                    oskar_telescope_station_const(tel, i);
            double lon = oskar_station_lon_rad(station);
            double lat = oskar_station_lat_rad(station);
            double alt = oskar_station_alt_metres(station);
            double x_ecef, y_ecef, z_ecef, x_offset, y_offset, z_offset;

            if (type == OSKAR_DOUBLE)
            {
                x_offset = ((double*)x_)[i];
                y_offset = ((double*)y_)[i];
                z_offset = ((double*)z_)[i];
            }
            else
            {
                x_offset = (double)((float*)x_)[i];
                y_offset = (double)((float*)y_)[i];
                z_offset = (double)((float*)z_)[i];
            }

            oskar_convert_offset_ecef_to_ecef(1, &x_offset, &y_offset,
                    &z_offset, lon, lat, alt, &x_ecef, &y_ecef, &z_ecef);
            double last = gast + lon;

            if (type == OSKAR_DOUBLE)
            {
                oskar_convert_apparent_ra_dec_to_enu_directions_d(num_sources,
                        oskar_mem_double_const(oskar_sky_ra_rad_const(sky), &status),
                        oskar_mem_double_const(oskar_sky_dec_rad_const(sky), &status),
                        last, lat, oskar_mem_double(hor_x, &status),
                        oskar_mem_double(hor_y, &status),
                        oskar_mem_double(hor_z, &status));
            }
            else
            {
                oskar_convert_apparent_ra_dec_to_enu_directions_f(num_sources,
                        oskar_mem_float_const(oskar_sky_ra_rad_const(sky), &status),
                        oskar_mem_float_const(oskar_sky_dec_rad_const(sky), &status),
                        last, lat, oskar_mem_float(hor_x, &status),
                        oskar_mem_float(hor_y, &status),
                        oskar_mem_float(hor_z, &status));
            }

            int offset = i * num_sources;
            oskar_mem_set_alias(pp_st_lon, pp_lon, offset, num_sources,
                    &status);
            oskar_mem_set_alias(pp_st_lat, pp_lat, offset, num_sources,
                    &status);
            oskar_mem_set_alias(pp_st_rel_path, pp_rel_path, offset,
                    num_sources, &status);
            oskar_evaluate_pierce_points(pp_st_lon, pp_st_lat, pp_st_rel_path,
                    x_ecef, y_ecef, z_ecef, screen_height_m,
                    num_sources, hor_x, hor_y, hor_z, &status);
        } // Loop over stations.

        if (status != 0)
            continue;

        int index = t; // could be = (num_times * f) + t if we have frequency data
        int num_fields = 3;
        int num_field_tags = 4;
        double freq_hz = 0.0;
        int freq_idx = 0;

        // Write the header TAGS
        oskar_binary_write_int(h, GRP, TIME_IDX, index, t, &status);
        oskar_binary_write_double(h, GRP, FREQ_IDX, index, freq_idx, &status);
        oskar_binary_write_double(h, GRP, TIME_MJD_UTC, index, t_dump, &status);
        oskar_binary_write_double(h, GRP, FREQ_HZ, index, freq_hz, &status);
        oskar_binary_write_int(h, GRP, NUM_FIELDS, index, num_fields, &status);
        oskar_binary_write_int(h, GRP, NUM_FIELD_TAGS, index, num_field_tags,
                &status);

        // Write data TAGS (fields)
        int field, tagID;
        field = 0;
        tagID = HEADER_OFFSET + (num_field_tags * field);
        oskar_binary_write_mem(h, pp_lon, GRP, tagID + DATA,
                index, 0, &status);
        oskar_binary_write_mem(h, dims, GRP, tagID  + DIMS,
                index, 0, &status);
        oskar_binary_write(h, OSKAR_CHAR, GRP, tagID + LABEL,
                index, label1.size()+1, label1.c_str(), &status);
        oskar_binary_write(h, OSKAR_CHAR, GRP, tagID + UNITS,
                index, units.size()+1, units.c_str(), &status);
        field = 1;
        tagID = HEADER_OFFSET + (num_field_tags * field);
        oskar_binary_write_mem(h, pp_lat, GRP, tagID + DATA,
                index, 0, &status);
        oskar_binary_write_mem(h, dims, GRP, tagID  + DIMS,
                index, 0, &status);
        oskar_binary_write(h, OSKAR_CHAR, GRP, tagID + LABEL,
                index, label2.size()+1, label2.c_str(), &status);
        oskar_binary_write(h, OSKAR_CHAR, GRP, tagID + UNITS,
                index, units.size()+1, units.c_str(), &status);
        field = 2;
        tagID = HEADER_OFFSET + (num_field_tags * field);
        oskar_binary_write_mem(h, pp_rel_path, GRP, tagID + DATA,
                index, 0, &status);
        oskar_binary_write_mem(h, dims, GRP, tagID  + DIMS,
                index, 0, &status);
        oskar_binary_write(h, OSKAR_CHAR, GRP, tagID + LABEL,
                index, label3.size()+1, label3.c_str(), &status);
        oskar_binary_write(h, OSKAR_CHAR, GRP, tagID + UNITS,
                index, units2.size()+1, units2.c_str(), &status);
    } // Loop over times

    // Close the OSKAR binary file.
    oskar_binary_free(h);

    // clean up memory
    oskar_mem_free(hor_x, &status);
    oskar_mem_free(hor_y, &status);
    oskar_mem_free(hor_z, &status);
    oskar_mem_free(pp_lon, &status);
    oskar_mem_free(pp_lat, &status);
    oskar_mem_free(pp_rel_path, &status);
    oskar_mem_free(pp_st_lon, &status);
    oskar_mem_free(pp_st_lat, &status);
    oskar_mem_free(pp_st_rel_path, &status);
    oskar_mem_free(dims, &status);
    oskar_telescope_free(tel, &status);
    oskar_sky_free(sky, &status);

    // Check for errors.
    if (status)
        oskar_log_error(log, "Run failed: %s.", oskar_get_error_string(status));
    oskar_log_free(log);

    return status;
}
void oskar_evaluate_station_beam(int num_points,
        int coord_type, oskar_Mem* x, oskar_Mem* y, oskar_Mem* z,
        double norm_ra_rad, double norm_dec_rad, const oskar_Station* station,
        oskar_StationWork* work, int time_index, double frequency_hz,
        double GAST, int offset_out, oskar_Mem* beam, int* status)
{
    oskar_Mem* out;
    const size_t num_points_orig = (size_t)num_points;
    if (*status) return;

    /* Set output beam array to work buffer. */
    out = oskar_station_work_beam_out(work, beam, num_points_orig, status);

    /* Check that the arrays have enough space to add an extra source at the
     * end (for normalisation). We don't want to reallocate here, since that
     * will be slow to do each time: must simply ensure that we pass input
     * arrays that are large enough.
     * The normalisation doesn't need to happen if the station has an
     * isotropic beam. */
    const int normalise = oskar_station_normalise_final_beam(station) &&
            (oskar_station_type(station) != OSKAR_STATION_TYPE_ISOTROPIC);
    if (normalise)
    {
        /* Increment number of points. */
        num_points++;

        /* Check the input arrays are big enough to hold the new source. */
        if ((int)oskar_mem_length(x) < num_points ||
                (int)oskar_mem_length(y) < num_points ||
                (int)oskar_mem_length(z) < num_points)
        {
            *status = OSKAR_ERR_DIMENSION_MISMATCH;
            return;
        }

        /* Get the beam direction in the appropriate coordinate system. */
        const int bypass = (coord_type != OSKAR_ENU_DIRECTIONS);
        const double ha0 = GAST + oskar_station_lon_rad(station) - norm_ra_rad;
        const double lat = oskar_station_lat_rad(station);
        oskar_convert_relative_directions_to_enu_directions(1, bypass, 0,
                1, 0, 0, 0, ha0, norm_dec_rad, lat, num_points - 1, x, y, z,
                status);
    }

    /* Evaluate the station beam for the given directions. */
    if (coord_type == OSKAR_ENU_DIRECTIONS)
        evaluate_station_beam_enu_directions(out, num_points, x, y, z,
                station, work, time_index, frequency_hz, GAST, status);
    else if (coord_type == OSKAR_RELATIVE_DIRECTIONS)
        evaluate_station_beam_relative_directions(out, num_points, x, y, z,
                station, work, time_index, frequency_hz, GAST, status);
    else
        *status = OSKAR_ERR_INVALID_ARGUMENT;

    /* Scale beam pattern by amplitude at the last source if required. */
    if (normalise)
        oskar_mem_normalise(out, 0, oskar_mem_length(out),
                num_points - 1, status);

    /* Copy output beam data. */
    oskar_mem_copy_contents(beam, out, offset_out, 0, num_points_orig, status);
}
void oskar_evaluate_beam_horizon_direction(double* x, double* y, double* z,
        const oskar_Station* station, const double gast, int* status)
{
    int beam_coord_type;
    double beam_lon, beam_lat;

    /* Check if safe to proceed. */
    if (*status) return;

    /* Get direction cosines in horizontal coordinates. */
    beam_coord_type = oskar_station_beam_coord_type(station);
    beam_lon = oskar_station_beam_lon_rad(station);
    beam_lat = oskar_station_beam_lat_rad(station);

    if (beam_coord_type == OSKAR_SPHERICAL_TYPE_EQUATORIAL)
    {
        double lon, lat, last;
        lon = oskar_station_lon_rad(station);
        lat = oskar_station_lat_rad(station);
        last = gast + lon; /* Local Apparent Sidereal Time, in radians. */
        oskar_convert_apparent_ra_dec_to_enu_directions_d(1, &beam_lon,
                &beam_lat, last, lat, x, y, z);
    }
    else if (beam_coord_type == OSKAR_SPHERICAL_TYPE_AZEL)
    {
        /* Convert AZEL to direction cosines. */
        double cos_lat;
        cos_lat = cos(beam_lat);
        *x = cos_lat * sin(beam_lon);
        *y = cos_lat * cos(beam_lon);
        *z = sin(beam_lat);
    }
    else
    {
        *status = OSKAR_ERR_INVALID_ARGUMENT;
    }

    /* Check if the beam direction needs to be one of a set of
     * allowed (az,el) directions. */
    if (oskar_station_num_permitted_beams(station) > 0)
    {
        int i, n, min_index = 0;
        double az, el, cos_el, min_dist = DBL_MAX;
        const double *p_az, *p_el;

        /* Convert current direction cosines to azimuth, elevation. */
        az = atan2(*x, *y);
        el = atan2(*z, sqrt(*x * *x + *y * *y));

        /* Get pointers to permitted beam data. */
        n = oskar_station_num_permitted_beams(station);
        p_az = oskar_mem_double_const(
                oskar_station_permitted_beam_az_rad_const(station),
                status);
        p_el = oskar_mem_double_const(
                oskar_station_permitted_beam_el_rad_const(station),
                status);

        /* Loop over permitted beams. */
        for (i = 0; i < n; ++i)
        {
            double dist;
            dist = oskar_angular_distance(p_az[i], az, p_el[i], el);
            if (dist < min_dist)
            {
                min_dist = dist;
                min_index = i;
            }
        }

        /* Select beam azimuth and elevation based on minimum distance. */
        az = p_az[min_index];
        el = p_el[min_index];

        /* Set new direction cosines. */
        cos_el = cos(el);
        *x = cos_el * sin(az);
        *y = cos_el * cos(az);
        *z = sin(el);
    }
}
Esempio n. 10
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/* Wrapper. */
void oskar_evaluate_jones_R(oskar_Jones* R, int num_sources,
        const oskar_Mem* ra_rad, const oskar_Mem* dec_rad,
        const oskar_Telescope* telescope, double gast, int* status)
{
    int i, n, num_stations, jones_type, base_type, location;
    double latitude, lst;
    oskar_Mem *R_station;

    /* Check if safe to proceed. */
    if (*status) return;

    /* Get the Jones matrix block meta-data. */
    jones_type = oskar_jones_type(R);
    base_type = oskar_type_precision(jones_type);
    location = oskar_jones_mem_location(R);
    num_stations = oskar_jones_num_stations(R);
    n = (oskar_telescope_allow_station_beam_duplication(telescope) ? 1 : num_stations);

    /* Check that the data dimensions are OK. */
    if (num_sources > (int)oskar_mem_length(ra_rad) ||
            num_sources > (int)oskar_mem_length(dec_rad) ||
            num_sources > oskar_jones_num_sources(R) ||
            num_stations != oskar_telescope_num_stations(telescope))
    {
        *status = OSKAR_ERR_DIMENSION_MISMATCH;
        return;
    }

    /* Check that the data is in the right location. */
    if (location != oskar_mem_location(ra_rad) ||
            location != oskar_mem_location(dec_rad))
    {
        *status = OSKAR_ERR_LOCATION_MISMATCH;
        return;
    }

    /* Check that the data is of the right type. */
    if (!oskar_type_is_matrix(jones_type))
    {
        *status = OSKAR_ERR_BAD_DATA_TYPE;
        return;
    }
    if (base_type != oskar_mem_precision(ra_rad) ||
            base_type != oskar_mem_precision(dec_rad))
    {
        *status = OSKAR_ERR_TYPE_MISMATCH;
        return;
    }

    /* Evaluate Jones matrix for each source for appropriate stations. */
    R_station = oskar_mem_create_alias(0, 0, 0, status);
    if (location == OSKAR_GPU)
    {
#ifdef OSKAR_HAVE_CUDA
        for (i = 0; i < n; ++i)
        {
            const oskar_Station* station;

            /* Get station data. */
            station = oskar_telescope_station_const(telescope, i);
            latitude = oskar_station_lat_rad(station);
            lst = gast + oskar_station_lon_rad(station);
            oskar_jones_get_station_pointer(R_station, R, i, status);

            /* Evaluate source parallactic angles. */
            if (base_type == OSKAR_SINGLE)
            {
                oskar_evaluate_jones_R_cuda_f(
                        oskar_mem_float4c(R_station, status), num_sources,
                        oskar_mem_float_const(ra_rad, status),
                        oskar_mem_float_const(dec_rad, status),
                        (float)latitude, (float)lst);
            }
            else if (base_type == OSKAR_DOUBLE)
            {
                oskar_evaluate_jones_R_cuda_d(
                        oskar_mem_double4c(R_station, status), num_sources,
                        oskar_mem_double_const(ra_rad, status),
                        oskar_mem_double_const(dec_rad, status),
                        latitude, lst);
            }
        }
        oskar_device_check_error(status);
#else
        *status = OSKAR_ERR_CUDA_NOT_AVAILABLE;
#endif
    }
    else if (location == OSKAR_CPU)
    {
        for (i = 0; i < n; ++i)
        {
            const oskar_Station* station;

            /* Get station data. */
            station = oskar_telescope_station_const(telescope, i);
            latitude = oskar_station_lat_rad(station);
            lst = gast + oskar_station_lon_rad(station);
            oskar_jones_get_station_pointer(R_station, R, i, status);

            /* Evaluate source parallactic angles. */
            if (base_type == OSKAR_SINGLE)
            {
                oskar_evaluate_jones_R_f(
                        oskar_mem_float4c(R_station, status), num_sources,
                        oskar_mem_float_const(ra_rad, status),
                        oskar_mem_float_const(dec_rad, status),
                        (float)latitude, (float)lst);
            }
            else if (base_type == OSKAR_DOUBLE)
            {
                oskar_evaluate_jones_R_d(
                        oskar_mem_double4c(R_station, status), num_sources,
                        oskar_mem_double_const(ra_rad, status),
                        oskar_mem_double_const(dec_rad, status),
                        latitude, lst);
            }
        }
    }

    /* Copy data for station 0 to stations 1 to n, if using a common sky. */
    if (oskar_telescope_allow_station_beam_duplication(telescope))
    {
        oskar_Mem* R0;
        R0 = oskar_mem_create_alias(0, 0, 0, status);
        oskar_jones_get_station_pointer(R0, R, 0, status);
        for (i = 1; i < num_stations; ++i)
        {
            oskar_jones_get_station_pointer(R_station, R, i, status);
            oskar_mem_copy_contents(R_station, R0, 0, 0,
                    oskar_mem_length(R0), status);
        }
        oskar_mem_free(R0, status);
    }
    oskar_mem_free(R_station, status);
}