void oskar_interferometer_set_sky_model(oskar_Interferometer* h,
        const oskar_Sky* sky, int* status)
{
    int i;
    if (*status || !h || !sky) return;

    /* Clear the old chunk set. */
    for (i = 0; i < h->num_sky_chunks; ++i)
        oskar_sky_free(h->sky_chunks[i], status);
    free(h->sky_chunks);
    h->sky_chunks = 0;
    h->num_sky_chunks = 0;

    /* Split up the sky model into chunks and store them. */
    h->num_sources_total = oskar_sky_num_sources(sky);
    if (h->num_sources_total > 0)
        oskar_sky_append_to_set(&h->num_sky_chunks, &h->sky_chunks,
                h->max_sources_per_chunk, sky, status);
    h->init_sky = 0;

    /* Print summary data. */
    if (h->log)
    {
        oskar_log_section(h->log, 'M', "Sky model summary");
        oskar_log_value(h->log, 'M', 0, "Num. sources", "%d",
                h->num_sources_total);
        oskar_log_value(h->log, 'M', 0, "Num. chunks", "%d",
                h->num_sky_chunks);
    }
}
Example #2
0
static PyObject* num_sources(PyObject* self, PyObject* args)
{
    oskar_Sky *h = 0;
    PyObject* capsule = 0;
    if (!PyArg_ParseTuple(args, "O", &capsule)) return 0;
    if (!(h = get_handle(capsule))) return 0;
    return Py_BuildValue("i", oskar_sky_num_sources(h));
}
Example #3
0
int benchmark(int num_stations, int num_sources, int type,
        int jones_type, int loc, int use_extended, int use_time_ave, int niter,
        std::vector<double>& times)
{
    int status = 0;

    oskar_Timer* timer;
    timer = oskar_timer_create(loc == OSKAR_GPU ?
            OSKAR_TIMER_CUDA : OSKAR_TIMER_OMP);

    // Set up a test sky model, telescope model and Jones matrices.
    oskar_Telescope* tel = oskar_telescope_create(type, loc,
            num_stations, &status);
    oskar_Sky* sky = oskar_sky_create(type, loc, num_sources, &status);
    oskar_Jones* J = oskar_jones_create(jones_type, loc, num_stations,
            num_sources, &status);

    oskar_telescope_set_channel_bandwidth(tel, 1e6);
    oskar_telescope_set_time_average(tel, (double) use_time_ave);
    oskar_sky_set_use_extended(sky, use_extended);

    // Memory for visibility coordinates and output visibility slice.
    oskar_Mem *vis, *u, *v, *w;
    vis = oskar_mem_create(jones_type, loc, oskar_telescope_num_baselines(tel),
            &status);
    u = oskar_mem_create(type, loc, num_stations, &status);
    v = oskar_mem_create(type, loc, num_stations, &status);
    w = oskar_mem_create(type, loc, num_stations, &status);

    // Run benchmark.
    times.resize(niter);
    for (int i = 0; i < niter; ++i)
    {
        oskar_timer_start(timer);
        oskar_cross_correlate(vis, oskar_sky_num_sources(sky), J, sky, tel, u, v, w,
                0.0, 100e6, &status);
        times[i] = oskar_timer_elapsed(timer);
    }

    // Free memory.
    oskar_mem_free(u, &status);
    oskar_mem_free(v, &status);
    oskar_mem_free(w, &status);
    oskar_mem_free(vis, &status);
    oskar_jones_free(J, &status);
    oskar_telescope_free(tel, &status);
    oskar_sky_free(sky, &status);
    oskar_timer_free(timer);
    return status;
}
Example #4
0
static void set_pixel(oskar_Sky* sky, int i, int x, int y, double val,
        const double crval[2], const double crpix[2], const double cdelt[2],
        double image_freq_hz, double spectral_index, int* status)
{
    double ra, dec, l, m;

    /* Convert pixel positions to RA and Dec values. */
    l = cdelt[0] * (x + 1 - crpix[0]);
    m = cdelt[1] * (y + 1 - crpix[1]);
    oskar_convert_relative_directions_to_lon_lat_2d_d(1,
            &l, &m, crval[0], crval[1], &ra, &dec);

    /* Store pixel data in sky model. */
    if (oskar_sky_num_sources(sky) <= i)
        oskar_sky_resize(sky, i + 1000, status);
    oskar_sky_set_source(sky, i, ra, dec, val, 0.0, 0.0, 0.0,
            image_freq_hz, spectral_index, 0.0, 0.0, 0.0, 0.0, status);
}
Example #5
0
void oskar_simulator_set_sky_model(oskar_Simulator* h, const oskar_Sky* sky,
        int max_sources_per_chunk, int* status)
{
    int i;
    if (*status) return;

    /* Clear the old chunk set. */
    for (i = 0; i < h->num_sky_chunks; ++i)
        oskar_sky_free(h->sky_chunks[i], status);
    free(h->sky_chunks);
    h->sky_chunks = 0;
    h->num_sky_chunks = 0;

    /* Split up the sky model into chunks and store them. */
    h->max_sources_per_chunk = max_sources_per_chunk;
    if (oskar_sky_num_sources(sky) > 0)
        oskar_sky_append_to_set(&h->num_sky_chunks, &h->sky_chunks,
                max_sources_per_chunk, sky, status);
    h->init_sky = 0;
}
Example #6
0
static void sim_baselines(oskar_Simulator* h, DeviceData* d, oskar_Sky* sky,
        int channel_index_block, int time_index_block,
        int time_index_simulation, int* status)
{
    int num_baselines, num_stations, num_src, num_times_block, num_channels;
    double dt_dump_days, t_start, t_dump, gast, frequency, ra0, dec0;
    const oskar_Mem *x, *y, *z;
    oskar_Mem* alias = 0;

    /* Get dimensions. */
    num_baselines   = oskar_telescope_num_baselines(d->tel);
    num_stations    = oskar_telescope_num_stations(d->tel);
    num_src         = oskar_sky_num_sources(sky);
    num_times_block = oskar_vis_block_num_times(d->vis_block);
    num_channels    = oskar_vis_block_num_channels(d->vis_block);

    /* Return if there are no sources in the chunk,
     * or if block time index requested is outside the valid range. */
    if (num_src == 0 || time_index_block >= num_times_block) return;

    /* Get the time and frequency of the visibility slice being simulated. */
    dt_dump_days = h->time_inc_sec / 86400.0;
    t_start = h->time_start_mjd_utc;
    t_dump = t_start + dt_dump_days * (time_index_simulation + 0.5);
    gast = oskar_convert_mjd_to_gast_fast(t_dump);
    frequency = h->freq_start_hz + channel_index_block * h->freq_inc_hz;

    /* Scale source fluxes with spectral index and rotation measure. */
    oskar_sky_scale_flux_with_frequency(sky, frequency, status);

    /* Evaluate station u,v,w coordinates. */
    ra0 = oskar_telescope_phase_centre_ra_rad(d->tel);
    dec0 = oskar_telescope_phase_centre_dec_rad(d->tel);
    x = oskar_telescope_station_true_x_offset_ecef_metres_const(d->tel);
    y = oskar_telescope_station_true_y_offset_ecef_metres_const(d->tel);
    z = oskar_telescope_station_true_z_offset_ecef_metres_const(d->tel);
    oskar_convert_ecef_to_station_uvw(num_stations, x, y, z, ra0, dec0, gast,
            d->u, d->v, d->w, status);

    /* Set dimensions of Jones matrices. */
    if (d->R)
        oskar_jones_set_size(d->R, num_stations, num_src, status);
    if (d->Z)
        oskar_jones_set_size(d->Z, num_stations, num_src, status);
    oskar_jones_set_size(d->J, num_stations, num_src, status);
    oskar_jones_set_size(d->E, num_stations, num_src, status);
    oskar_jones_set_size(d->K, num_stations, num_src, status);

    /* Evaluate station beam (Jones E: may be matrix). */
    oskar_timer_resume(d->tmr_E);
    oskar_evaluate_jones_E(d->E, num_src, OSKAR_RELATIVE_DIRECTIONS,
            oskar_sky_l(sky), oskar_sky_m(sky), oskar_sky_n(sky), d->tel,
            gast, frequency, d->station_work, time_index_simulation, status);
    oskar_timer_pause(d->tmr_E);

#if 0
    /* Evaluate ionospheric phase (Jones Z: scalar) and join with Jones E.
     * NOTE this is currently only a CPU implementation. */
    if (d->Z)
    {
        oskar_evaluate_jones_Z(d->Z, num_src, sky, d->tel,
                &settings->ionosphere, gast, frequency, &(d->workJonesZ),
                status);
        oskar_timer_resume(d->tmr_join);
        oskar_jones_join(d->E, d->Z, d->E, status);
        oskar_timer_pause(d->tmr_join);
    }
#endif

    /* Evaluate parallactic angle (Jones R: matrix), and join with Jones Z*E.
     * TODO Move this into station beam evaluation instead. */
    if (d->R)
    {
        oskar_timer_resume(d->tmr_E);
        oskar_evaluate_jones_R(d->R, num_src, oskar_sky_ra_rad_const(sky),
                oskar_sky_dec_rad_const(sky), d->tel, gast, status);
        oskar_timer_pause(d->tmr_E);
        oskar_timer_resume(d->tmr_join);
        oskar_jones_join(d->R, d->E, d->R, status);
        oskar_timer_pause(d->tmr_join);
    }

    /* Evaluate interferometer phase (Jones K: scalar). */
    oskar_timer_resume(d->tmr_K);
    oskar_evaluate_jones_K(d->K, num_src, oskar_sky_l_const(sky),
            oskar_sky_m_const(sky), oskar_sky_n_const(sky), d->u, d->v, d->w,
            frequency, oskar_sky_I_const(sky),
            h->source_min_jy, h->source_max_jy, status);
    oskar_timer_pause(d->tmr_K);

    /* Join Jones K with Jones Z*E. */
    oskar_timer_resume(d->tmr_join);
    oskar_jones_join(d->J, d->K, d->R ? d->R : d->E, status);
    oskar_timer_pause(d->tmr_join);

    /* Create alias for auto/cross-correlations. */
    oskar_timer_resume(d->tmr_correlate);
    alias = oskar_mem_create_alias(0, 0, 0, status);

    /* Auto-correlate for this time and channel. */
    if (oskar_vis_block_has_auto_correlations(d->vis_block))
    {
        oskar_mem_set_alias(alias,
                oskar_vis_block_auto_correlations(d->vis_block),
                num_stations *
                (num_channels * time_index_block + channel_index_block),
                num_stations, status);
        oskar_auto_correlate(alias, num_src, d->J, sky, status);
    }

    /* Cross-correlate for this time and channel. */
    if (oskar_vis_block_has_cross_correlations(d->vis_block))
    {
        oskar_mem_set_alias(alias,
                oskar_vis_block_cross_correlations(d->vis_block),
                num_baselines *
                (num_channels * time_index_block + channel_index_block),
                num_baselines, status);
        oskar_cross_correlate(alias, num_src, d->J, sky, d->tel,
                d->u, d->v, d->w, gast, frequency, status);
    }

    /* Free alias for auto/cross-correlations. */
    oskar_mem_free(alias, status);
    oskar_timer_pause(d->tmr_correlate);
}
Example #7
0
void oskar_simulator_run(oskar_Simulator* h, int* status)
{
    int i, num_threads = 1, num_vis_blocks;
    if (*status) return;

    /* Check the visibilities are going somewhere. */
    if (!h->vis_name
#ifndef OSKAR_NO_MS
            && !h->ms_name
#endif
    )
    {
        oskar_log_error(h->log, "No output file specified.");
#ifdef OSKAR_NO_MS
        if (h->ms_name)
            oskar_log_error(h->log,
                    "OSKAR was compiled without Measurement Set support.");
#endif
        *status = OSKAR_ERR_FILE_IO;
        return;
    }

    /* Initialise if required. */
    oskar_simulator_check_init(h, status);

    /* Get the number of visibility blocks to be processed. */
    num_vis_blocks = oskar_simulator_num_vis_blocks(h);

    /* Record memory usage. */
    if (h->log && !*status)
    {
        oskar_log_section(h->log, 'M', "Initial memory usage");
#ifdef OSKAR_HAVE_CUDA
        for (i = 0; i < h->num_gpus; ++i)
            oskar_cuda_mem_log(h->log, 0, h->gpu_ids[i]);
#endif
        system_mem_log(h->log);
        oskar_log_section(h->log, 'M', "Starting simulation...");
    }

    /* Start simulation timer. */
    oskar_timer_start(h->tmr_sim);

    /*-----------------------------------------------------------------------
     *-- START OF MULTITHREADED SIMULATION CODE -----------------------------
     *-----------------------------------------------------------------------*/
    /* Loop over blocks of observation time, running simulation and file
     * writing one block at a time. Simulation and file output are overlapped
     * by using double buffering, and a dedicated thread is used for file
     * output.
     *
     * Thread 0 is used for file writes.
     * Threads 1 to n (mapped to compute devices) do the simulation.
     *
     * Note that no write is launched on the first loop counter (as no
     * data are ready yet) and no simulation is performed for the last loop
     * counter (which corresponds to the last block + 1) as this iteration
     * simply writes the last block.
     */
#ifdef _OPENMP
    num_threads = h->num_devices + 1;
    omp_set_num_threads(num_threads);
    omp_set_nested(0);
#else
    oskar_log_warning(h->log, "OpenMP not found: Using one compute device.");
#endif

    oskar_simulator_reset_work_unit_index(h);
#pragma omp parallel
    {
        int b, thread_id = 0, device_id = 0;

        /* Get host thread ID and device ID. */
#ifdef _OPENMP
        thread_id = omp_get_thread_num();
        device_id = thread_id - 1;
#endif

        /* Loop over simulation time blocks (+1, for the last write). */
        for (b = 0; b < num_vis_blocks + 1; ++b)
        {
            if ((thread_id > 0 || num_threads == 1) && b < num_vis_blocks)
                oskar_simulator_run_block(h, b, device_id, status);
            if (thread_id == 0 && b > 0)
            {
                oskar_VisBlock* block;
                block = oskar_simulator_finalise_block(h, b - 1, status);
                oskar_simulator_write_block(h, block, b - 1, status);
            }

            /* Barrier 1: Reset work unit index. */
#pragma omp barrier
            if (thread_id == 0)
                oskar_simulator_reset_work_unit_index(h);

            /* Barrier 2: Synchronise before moving to the next block. */
#pragma omp barrier
            if (thread_id == 0 && b < num_vis_blocks && h->log && !*status)
                oskar_log_message(h->log, 'S', 0, "Block %*i/%i (%3.0f%%) "
                        "complete. Simulation time elapsed: %.3f s",
                        disp_width(num_vis_blocks), b+1, num_vis_blocks,
                        100.0 * (b+1) / (double)num_vis_blocks,
                        oskar_timer_elapsed(h->tmr_sim));
        }
    }
    /*-----------------------------------------------------------------------
     *-- END OF MULTITHREADED SIMULATION CODE -------------------------------
     *-----------------------------------------------------------------------*/

    /* Record memory usage. */
    if (h->log && !*status)
    {
        oskar_log_section(h->log, 'M', "Final memory usage");
#ifdef OSKAR_HAVE_CUDA
        for (i = 0; i < h->num_gpus; ++i)
            oskar_cuda_mem_log(h->log, 0, h->gpu_ids[i]);
#endif
        system_mem_log(h->log);
    }

    /* If there are sources in the simulation and the station beam is not
     * normalised to 1.0 at the phase centre, the values of noise RMS
     * may give a very unexpected S/N ratio!
     * The alternative would be to scale the noise to match the station
     * beam gain but that would require knowledge of the station beam
     * amplitude at the phase centre for each time and channel. */
    if (h->log && oskar_telescope_noise_enabled(h->tel) && !*status)
    {
        int have_sources, amp_calibrated;
        have_sources = (h->num_sky_chunks > 0 &&
                oskar_sky_num_sources(h->sky_chunks[0]) > 0);
        amp_calibrated = oskar_station_normalise_final_beam(
                oskar_telescope_station_const(h->tel, 0));
        if (have_sources && !amp_calibrated)
        {
            const char* a = "WARNING: System noise added to visibilities";
            const char* b = "without station beam normalisation enabled.";
            const char* c = "This will give an invalid signal to noise ratio.";
            oskar_log_line(h->log, 'W', ' '); oskar_log_line(h->log, 'W', '*');
            oskar_log_message(h->log, 'W', -1, a);
            oskar_log_message(h->log, 'W', -1, b);
            oskar_log_message(h->log, 'W', -1, c);
            oskar_log_line(h->log, 'W', '*'); oskar_log_line(h->log, 'W', ' ');
        }
    }

    /* Record times and summarise output files. */
    if (h->log && !*status)
    {
        size_t log_size = 0;
        char* log_data;
        oskar_log_set_value_width(h->log, 25);
        record_timing(h);
        oskar_log_section(h->log, 'M', "Simulation complete");
        oskar_log_message(h->log, 'M', 0, "Output(s):");
        if (h->vis_name)
            oskar_log_value(h->log, 'M', 1,
                    "OSKAR binary file", "%s", h->vis_name);
        if (h->ms_name)
            oskar_log_value(h->log, 'M', 1,
                    "Measurement Set", "%s", h->ms_name);

        /* Write simulation log to the output files. */
        log_data = oskar_log_file_data(h->log, &log_size);
#ifndef OSKAR_NO_MS
        if (h->ms)
            oskar_ms_add_history(h->ms, "OSKAR_LOG", log_data, log_size);
#endif
        if (h->vis)
            oskar_binary_write(h->vis, OSKAR_CHAR, OSKAR_TAG_GROUP_RUN,
                    OSKAR_TAG_RUN_LOG, 0, log_size, log_data, status);
        free(log_data);
    }

    /* Finalise. */
    oskar_simulator_finalise(h, status);
}
Example #8
0
void oskar_simulator_run_block(oskar_Simulator* h, int block_index,
        int device_id, int* status)
{
    double obs_start_mjd, dt_dump_days;
    int i_active, time_index_start, time_index_end;
    int num_channels, num_times_block, total_chunks, total_times;
    DeviceData* d;
    if (*status) return;

    /* Check that initialisation has happened. We can't initialise here,
     * as we're already multi-threaded at this point. */
    if (!h->header)
    {
        *status = OSKAR_ERR_MEMORY_NOT_ALLOCATED;
        oskar_log_error(h->log, "Simulator not initalised. "
                "Call oskar_simulator_check_init() first.");
        return;
    }

#ifdef _OPENMP
    if (!h->coords_only)
    {
        /* Disable any nested parallelism. */
        omp_set_num_threads(1);
        omp_set_nested(0);
    }
#endif

    /* Set the GPU to use. (Supposed to be a very low-overhead call.) */
    if (device_id >= 0 && device_id < h->num_gpus)
        oskar_device_set(h->gpu_ids[device_id], status);

    /* Clear the visibility block. */
    i_active = block_index % 2; /* Index of the active buffer. */
    d = &(h->d[device_id]);
    oskar_timer_resume(d->tmr_compute);
    oskar_vis_block_clear(d->vis_block, status);

    /* Set the visibility block meta-data. */
    total_chunks = h->num_sky_chunks;
    num_channels = h->num_channels;
    total_times = h->num_time_steps;
    obs_start_mjd = h->time_start_mjd_utc;
    dt_dump_days = h->time_inc_sec / 86400.0;
    time_index_start = block_index * h->max_times_per_block;
    time_index_end = time_index_start + h->max_times_per_block - 1;
    if (time_index_end >= total_times)
        time_index_end = total_times - 1;
    num_times_block = 1 + time_index_end - time_index_start;

    /* Set the number of active times in the block. */
    oskar_vis_block_set_num_times(d->vis_block, num_times_block, status);
    oskar_vis_block_set_start_time_index(d->vis_block, time_index_start);

    /* Go though all possible work units in the block. A work unit is defined
     * as the simulation for one time and one sky chunk. */
    while (!h->coords_only)
    {
        oskar_Sky* sky;
        int i_work_unit, i_chunk, i_time, i_channel, sim_time_idx;

        oskar_mutex_lock(h->mutex);
        i_work_unit = (h->work_unit_index)++;
        oskar_mutex_unlock(h->mutex);
        if ((i_work_unit >= num_times_block * total_chunks) || *status) break;

        /* Convert slice index to chunk/time index. */
        i_chunk      = i_work_unit / num_times_block;
        i_time       = i_work_unit - i_chunk * num_times_block;
        sim_time_idx = time_index_start + i_time;

        /* Copy sky chunk to device only if different from the previous one. */
        if (i_chunk != d->previous_chunk_index)
        {
            oskar_timer_resume(d->tmr_copy);
            oskar_sky_copy(d->chunk, h->sky_chunks[i_chunk], status);
            oskar_timer_pause(d->tmr_copy);
        }
        sky = h->apply_horizon_clip ? d->chunk_clip : d->chunk;

        /* Apply horizon clip if required. */
        if (h->apply_horizon_clip)
        {
            double gast, mjd;
            mjd = obs_start_mjd + dt_dump_days * (sim_time_idx + 0.5);
            gast = oskar_convert_mjd_to_gast_fast(mjd);
            oskar_timer_resume(d->tmr_clip);
            oskar_sky_horizon_clip(d->chunk_clip, d->chunk, d->tel, gast,
                    d->station_work, status);
            oskar_timer_pause(d->tmr_clip);
        }

        /* Simulate all baselines for all channels for this time and chunk. */
        for (i_channel = 0; i_channel < num_channels; ++i_channel)
        {
            if (*status) break;
            if (h->log)
            {
                oskar_mutex_lock(h->mutex);
                oskar_log_message(h->log, 'S', 1, "Time %*i/%i, "
                        "Chunk %*i/%i, Channel %*i/%i [Device %i, %i sources]",
                        disp_width(total_times), sim_time_idx + 1, total_times,
                        disp_width(total_chunks), i_chunk + 1, total_chunks,
                        disp_width(num_channels), i_channel + 1, num_channels,
                        device_id, oskar_sky_num_sources(sky));
                oskar_mutex_unlock(h->mutex);
            }
            sim_baselines(h, d, sky, i_channel, i_time, sim_time_idx, status);
        }
        d->previous_chunk_index = i_chunk;
    }

    /* Copy the visibility block to host memory. */
    oskar_timer_resume(d->tmr_copy);
    oskar_vis_block_copy(d->vis_block_cpu[i_active], d->vis_block, status);
    oskar_timer_pause(d->tmr_copy);
    oskar_timer_pause(d->tmr_compute);
}
/* Wrapper. */
void oskar_sky_scale_flux_with_frequency(oskar_Sky* sky, double frequency,
        int* status)
{
    int type, location, num_sources;

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

    /* Get the type, location and dimensions. */
    type = oskar_sky_precision(sky);
    location = oskar_sky_mem_location(sky);
    num_sources = oskar_sky_num_sources(sky);

    /* Scale the flux values. */
    if (location == OSKAR_CPU)
    {
        if (type == OSKAR_SINGLE)
            oskar_sky_scale_flux_with_frequency_f(num_sources, frequency,
                    oskar_mem_float(oskar_sky_I(sky), status),
                    oskar_mem_float(oskar_sky_Q(sky), status),
                    oskar_mem_float(oskar_sky_U(sky), status),
                    oskar_mem_float(oskar_sky_V(sky), status),
                    oskar_mem_float(oskar_sky_reference_freq_hz(sky), status),
                    oskar_mem_float_const(
                            oskar_sky_spectral_index_const(sky), status),
                    oskar_mem_float_const(
                            oskar_sky_rotation_measure_rad_const(sky), status));
        else if (type == OSKAR_DOUBLE)
            oskar_sky_scale_flux_with_frequency_d(num_sources, frequency,
                    oskar_mem_double(oskar_sky_I(sky), status),
                    oskar_mem_double(oskar_sky_Q(sky), status),
                    oskar_mem_double(oskar_sky_U(sky), status),
                    oskar_mem_double(oskar_sky_V(sky), status),
                    oskar_mem_double(oskar_sky_reference_freq_hz(sky), status),
                    oskar_mem_double_const(
                            oskar_sky_spectral_index_const(sky), status),
                    oskar_mem_double_const(
                            oskar_sky_rotation_measure_rad_const(sky), status));
        else
            *status = OSKAR_ERR_BAD_DATA_TYPE;
    }
    else if (location == OSKAR_GPU)
    {
#ifdef OSKAR_HAVE_CUDA
        if (type == OSKAR_SINGLE)
            oskar_sky_scale_flux_with_frequency_cuda_f(num_sources, frequency,
                    oskar_mem_float(oskar_sky_I(sky), status),
                    oskar_mem_float(oskar_sky_Q(sky), status),
                    oskar_mem_float(oskar_sky_U(sky), status),
                    oskar_mem_float(oskar_sky_V(sky), status),
                    oskar_mem_float(oskar_sky_reference_freq_hz(sky), status),
                    oskar_mem_float_const(
                            oskar_sky_spectral_index_const(sky), status),
                    oskar_mem_float_const(
                            oskar_sky_rotation_measure_rad_const(sky), status));
        else if (type == OSKAR_DOUBLE)
            oskar_sky_scale_flux_with_frequency_cuda_d(num_sources, frequency,
                    oskar_mem_double(oskar_sky_I(sky), status),
                    oskar_mem_double(oskar_sky_Q(sky), status),
                    oskar_mem_double(oskar_sky_U(sky), status),
                    oskar_mem_double(oskar_sky_V(sky), status),
                    oskar_mem_double(oskar_sky_reference_freq_hz(sky), status),
                    oskar_mem_double_const(
                            oskar_sky_spectral_index_const(sky), status),
                    oskar_mem_double_const(
                            oskar_sky_rotation_measure_rad_const(sky), status));
        else
            *status = OSKAR_ERR_BAD_DATA_TYPE;
        oskar_device_check_error(status);
#else
        *status = OSKAR_ERR_CUDA_NOT_AVAILABLE;
#endif
    }
    else if (location & OSKAR_CL)
    {
#ifdef OSKAR_HAVE_OPENCL
        cl_event event;
        cl_kernel k = 0;
        cl_int error, num;
        cl_uint arg = 0;
        size_t global_size, local_size;
        if (type == OSKAR_DOUBLE)
            k = oskar_cl_kernel("scale_flux_with_frequency_double");
        else if (type == OSKAR_SINGLE)
            k = oskar_cl_kernel("scale_flux_with_frequency_float");
        else
        {
            *status = OSKAR_ERR_BAD_DATA_TYPE;
            return;
        }
        if (!k)
        {
            *status = OSKAR_ERR_FUNCTION_NOT_AVAILABLE;
            return;
        }

        /* Set kernel arguments. */
        num = (cl_int) num_sources;
        error = clSetKernelArg(k, arg++, sizeof(cl_int), &num);
        if (type == OSKAR_SINGLE)
        {
            const cl_float freq = (cl_float) frequency;
            error |= clSetKernelArg(k, arg++, sizeof(cl_float), &freq);
        }
        else if (type == OSKAR_DOUBLE)
        {
            const cl_double freq = (cl_double) frequency;
            error |= clSetKernelArg(k, arg++, sizeof(cl_double), &freq);
        }
        error |= clSetKernelArg(k, arg++, sizeof(cl_mem),
                oskar_mem_cl_buffer(oskar_sky_I(sky), status));
        error |= clSetKernelArg(k, arg++, sizeof(cl_mem),
                oskar_mem_cl_buffer(oskar_sky_Q(sky), status));
        error |= clSetKernelArg(k, arg++, sizeof(cl_mem),
                oskar_mem_cl_buffer(oskar_sky_U(sky), status));
        error |= clSetKernelArg(k, arg++, sizeof(cl_mem),
                oskar_mem_cl_buffer(oskar_sky_V(sky), status));
        error |= clSetKernelArg(k, arg++, sizeof(cl_mem),
                oskar_mem_cl_buffer(oskar_sky_reference_freq_hz(sky), status));
        error |= clSetKernelArg(k, arg++, sizeof(cl_mem),
                oskar_mem_cl_buffer_const(oskar_sky_spectral_index_const(sky), status));
        error |= clSetKernelArg(k, arg++, sizeof(cl_mem),
                oskar_mem_cl_buffer_const(oskar_sky_rotation_measure_rad_const(sky), status));
        if (error != CL_SUCCESS)
        {
            *status = OSKAR_ERR_INVALID_ARGUMENT;
            return;
        }

        /* Launch kernel on current command queue. */
        local_size = oskar_cl_is_gpu() ? 256 : 128;
        global_size = ((num + local_size - 1) / local_size) * local_size;
        error = clEnqueueNDRangeKernel(oskar_cl_command_queue(), k, 1, NULL,
                &global_size, &local_size, 0, NULL, &event);
        if (error != CL_SUCCESS)
            *status = OSKAR_ERR_KERNEL_LAUNCH_FAILURE;
#else
        *status = OSKAR_ERR_OPENCL_NOT_AVAILABLE;
#endif
    }
    else
        *status = OSKAR_ERR_BAD_LOCATION;
}
void oskar_interferometer_run(oskar_Interferometer* h, int* status)
{
    int i, num_threads;
    oskar_Thread** threads = 0;
    ThreadArgs* args = 0;
    if (*status || !h) return;

    /* Check the visibilities are going somewhere. */
    if (!h->vis_name
#ifndef OSKAR_NO_MS
            && !h->ms_name
#endif
    )
    {
        oskar_log_error(h->log, "No output file specified.");
#ifdef OSKAR_NO_MS
        if (h->ms_name)
            oskar_log_error(h->log,
                    "OSKAR was compiled without Measurement Set support.");
#endif
        *status = OSKAR_ERR_FILE_IO;
        return;
    }

    /* Initialise if required. */
    oskar_interferometer_check_init(h, status);

    /* Set up worker threads. */
    num_threads = h->num_devices + 1;
    oskar_barrier_set_num_threads(h->barrier, num_threads);
    threads = (oskar_Thread**) calloc(num_threads, sizeof(oskar_Thread*));
    args = (ThreadArgs*) calloc(num_threads, sizeof(ThreadArgs));
    for (i = 0; i < num_threads; ++i)
    {
        args[i].h = h;
        args[i].num_threads = num_threads;
        args[i].thread_id = i;
    }

    /* Record memory usage. */
    if (h->log && !*status)
    {
        oskar_log_section(h->log, 'M', "Initial memory usage");
#ifdef OSKAR_HAVE_CUDA
        for (i = 0; i < h->num_gpus; ++i)
            oskar_cuda_mem_log(h->log, 0, h->gpu_ids[i]);
#endif
        system_mem_log(h->log);
        oskar_log_section(h->log, 'M', "Starting simulation...");
    }

    /* Start simulation timer. */
    oskar_timer_start(h->tmr_sim);

    /* Set status code. */
    h->status = *status;

    /* Start the worker threads. */
    oskar_interferometer_reset_work_unit_index(h);
    for (i = 0; i < num_threads; ++i)
        threads[i] = oskar_thread_create(run_blocks, (void*)&args[i], 0);

    /* Wait for worker threads to finish. */
    for (i = 0; i < num_threads; ++i)
    {
        oskar_thread_join(threads[i]);
        oskar_thread_free(threads[i]);
    }
    free(threads);
    free(args);

    /* Get status code. */
    *status = h->status;

    /* Record memory usage. */
    if (h->log && !*status)
    {
        oskar_log_section(h->log, 'M', "Final memory usage");
#ifdef OSKAR_HAVE_CUDA
        for (i = 0; i < h->num_gpus; ++i)
            oskar_cuda_mem_log(h->log, 0, h->gpu_ids[i]);
#endif
        system_mem_log(h->log);
    }

    /* If there are sources in the simulation and the station beam is not
     * normalised to 1.0 at the phase centre, the values of noise RMS
     * may give a very unexpected S/N ratio!
     * The alternative would be to scale the noise to match the station
     * beam gain but that would require knowledge of the station beam
     * amplitude at the phase centre for each time and channel. */
    if (h->log && oskar_telescope_noise_enabled(h->tel) && !*status)
    {
        int have_sources, amp_calibrated;
        have_sources = (h->num_sky_chunks > 0 &&
                oskar_sky_num_sources(h->sky_chunks[0]) > 0);
        amp_calibrated = oskar_station_normalise_final_beam(
                oskar_telescope_station_const(h->tel, 0));
        if (have_sources && !amp_calibrated)
        {
            const char* a = "WARNING: System noise added to visibilities";
            const char* b = "without station beam normalisation enabled.";
            const char* c = "This will give an invalid signal to noise ratio.";
            oskar_log_line(h->log, 'W', ' '); oskar_log_line(h->log, 'W', '*');
            oskar_log_message(h->log, 'W', -1, a);
            oskar_log_message(h->log, 'W', -1, b);
            oskar_log_message(h->log, 'W', -1, c);
            oskar_log_line(h->log, 'W', '*'); oskar_log_line(h->log, 'W', ' ');
        }
    }

    /* Record times and summarise output files. */
    if (h->log && !*status)
    {
        size_t log_size = 0;
        char* log_data;
        oskar_log_set_value_width(h->log, 25);
        record_timing(h);
        oskar_log_section(h->log, 'M', "Simulation complete");
        oskar_log_message(h->log, 'M', 0, "Output(s):");
        if (h->vis_name)
            oskar_log_value(h->log, 'M', 1,
                    "OSKAR binary file", "%s", h->vis_name);
        if (h->ms_name)
            oskar_log_value(h->log, 'M', 1,
                    "Measurement Set", "%s", h->ms_name);

        /* Write simulation log to the output files. */
        log_data = oskar_log_file_data(h->log, &log_size);
#ifndef OSKAR_NO_MS
        if (h->ms)
            oskar_ms_add_history(h->ms, "OSKAR_LOG", log_data, log_size);
#endif
        if (h->vis)
            oskar_binary_write(h->vis, OSKAR_CHAR, OSKAR_TAG_GROUP_RUN,
                    OSKAR_TAG_RUN_LOG, 0, log_size, log_data, status);
        free(log_data);
    }

    /* Finalise. */
    oskar_interferometer_finalise(h, status);
}
Example #11
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);
}
Example #12
0
    void runTest(int prec1, int prec2, int loc1, int loc2, int matrix,
            int extended, double time_average)
    {
        int num_baselines, status = 0, type;
        oskar_Mem *vis1, *vis2;
        oskar_Timer *timer1, *timer2;
        double time1, time2, frequency = 100e6;

        // Create the timers.
        timer1 = oskar_timer_create(loc1 == OSKAR_GPU ?
                OSKAR_TIMER_CUDA : OSKAR_TIMER_NATIVE);
        timer2 = oskar_timer_create(loc2 == OSKAR_GPU ?
                OSKAR_TIMER_CUDA : OSKAR_TIMER_NATIVE);

        // Run first part.
        createTestData(prec1, loc1, matrix);
        num_baselines = oskar_telescope_num_baselines(tel);
        type = prec1 | OSKAR_COMPLEX;
        if (matrix) type |= OSKAR_MATRIX;
        vis1 = oskar_mem_create(type, loc1, num_baselines, &status);
        oskar_mem_clear_contents(vis1, &status);
        ASSERT_EQ(0, status) << oskar_get_error_string(status);
        oskar_sky_set_use_extended(sky, extended);
        oskar_telescope_set_channel_bandwidth(tel, bandwidth);
        oskar_telescope_set_time_average(tel, time_average);
        oskar_timer_start(timer1);
        oskar_cross_correlate(vis1, oskar_sky_num_sources(sky), jones, sky,
                tel, u_, v_, w_, 1.0, frequency, &status);
        time1 = oskar_timer_elapsed(timer1);
        destroyTestData();
        ASSERT_EQ(0, status) << oskar_get_error_string(status);

        // Run second part.
        createTestData(prec2, loc2, matrix);
        num_baselines = oskar_telescope_num_baselines(tel);
        type = prec2 | OSKAR_COMPLEX;
        if (matrix) type |= OSKAR_MATRIX;
        vis2 = oskar_mem_create(type, loc2, num_baselines, &status);
        oskar_mem_clear_contents(vis2, &status);
        ASSERT_EQ(0, status) << oskar_get_error_string(status);
        oskar_sky_set_use_extended(sky, extended);
        oskar_telescope_set_channel_bandwidth(tel, bandwidth);
        oskar_telescope_set_time_average(tel, time_average);
        oskar_timer_start(timer2);
        oskar_cross_correlate(vis2, oskar_sky_num_sources(sky), jones, sky,
                tel, u_, v_, w_, 1.0, frequency, &status);
        time2 = oskar_timer_elapsed(timer2);
        destroyTestData();
        ASSERT_EQ(0, status) << oskar_get_error_string(status);

        // Destroy the timers.
        oskar_timer_free(timer1);
        oskar_timer_free(timer2);

        // Compare results.
        check_values(vis1, vis2);

        // Free memory.
        oskar_mem_free(vis1, &status);
        oskar_mem_free(vis2, &status);
        ASSERT_EQ(0, status) << oskar_get_error_string(status);

        // Record properties for test.
        RecordProperty("SourceType", extended ? "Gaussian" : "Point");
        RecordProperty("JonesType", matrix ? "Matrix" : "Scalar");
        RecordProperty("TimeSmearing", time_average == 0.0 ? "off" : "on");
        RecordProperty("Prec1", prec1 == OSKAR_SINGLE ? "Single" : "Double");
        RecordProperty("Loc1", loc1 == OSKAR_CPU ? "CPU" : "GPU");
        RecordProperty("Time1_ms", int(time1 * 1000));
        RecordProperty("Prec2", prec2 == OSKAR_SINGLE ? "Single" : "Double");
        RecordProperty("Loc2", loc2 == OSKAR_CPU ? "CPU" : "GPU");
        RecordProperty("Time2_ms", int(time2 * 1000));

#ifdef ALLOW_PRINTING
        // Print times.
        printf("  > %s. %s sources. Time smearing %s.\n",
                matrix ? "Matrix" : "Scalar",
                extended ? "Gaussian" : "Point",
                time_average == 0.0 ? "off" : "on");
        printf("    %s precision %s: %.2f ms, %s precision %s: %.2f ms\n",
                prec1 == OSKAR_SINGLE ? "Single" : "Double",
                loc1 == OSKAR_CPU ? "CPU" : "GPU",
                time1 * 1000.0,
                prec2 == OSKAR_SINGLE ? "Single" : "Double",
                loc2 == OSKAR_CPU ? "CPU" : "GPU",
                time2 * 1000.0);
#endif
    }
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;
}
Example #14
0
static PyObject* append_sources(PyObject* self, PyObject* args)
{
    oskar_Sky *h = 0;
    PyObject *obj[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
    oskar_Mem *ra_c, *dec_c, *I_c, *Q_c, *U_c, *V_c;
    oskar_Mem *ref_c, *spix_c, *rm_c, *maj_c, *min_c, *pa_c;
    PyArrayObject *ra = 0, *dec = 0, *I = 0, *Q = 0, *U = 0, *V = 0;
    PyArrayObject *ref = 0, *spix = 0, *rm = 0, *maj = 0, *min = 0, *pa = 0;
    int status = 0, npy_type, type, flags, num_sources, old_num;

    /* Parse inputs: RA, Dec, I, Q, U, V, ref, spix, rm, maj, min, pa. */
    if (!PyArg_ParseTuple(args, "OOOOOOOOOOOOO", &obj[0],
            &obj[1], &obj[2], &obj[3], &obj[4], &obj[5], &obj[6],
            &obj[7], &obj[8], &obj[9], &obj[10], &obj[11], &obj[12]))
        return 0;
    if (!(h = get_handle(obj[0]))) return 0;

    /* Make sure input objects are arrays. Convert if required. */
    flags = NPY_ARRAY_FORCECAST | NPY_ARRAY_IN_ARRAY;
    type = oskar_sky_precision(h);
    npy_type = numpy_type_from_oskar(type);
    ra   = (PyArrayObject*) PyArray_FROM_OTF(obj[1], npy_type, flags);
    dec  = (PyArrayObject*) PyArray_FROM_OTF(obj[2], npy_type, flags);
    I    = (PyArrayObject*) PyArray_FROM_OTF(obj[3], npy_type, flags);
    Q    = (PyArrayObject*) PyArray_FROM_OTF(obj[4], npy_type, flags);
    U    = (PyArrayObject*) PyArray_FROM_OTF(obj[5], npy_type, flags);
    V    = (PyArrayObject*) PyArray_FROM_OTF(obj[6], npy_type, flags);
    ref  = (PyArrayObject*) PyArray_FROM_OTF(obj[7], npy_type, flags);
    spix = (PyArrayObject*) PyArray_FROM_OTF(obj[8], npy_type, flags);
    rm   = (PyArrayObject*) PyArray_FROM_OTF(obj[9], npy_type, flags);
    maj  = (PyArrayObject*) PyArray_FROM_OTF(obj[10], npy_type, flags);
    min  = (PyArrayObject*) PyArray_FROM_OTF(obj[11], npy_type, flags);
    pa   = (PyArrayObject*) PyArray_FROM_OTF(obj[12], npy_type, flags);
    if (!ra || !dec || !I || !Q || !U || !V ||
            !ref || !spix || !rm || !maj || !min || !pa)
        goto fail;

    /* Check size of input arrays. */
    num_sources = (int) PyArray_SIZE(I);
    if (num_sources != (int) PyArray_SIZE(ra) ||
            num_sources != (int) PyArray_SIZE(dec) ||
            num_sources != (int) PyArray_SIZE(Q) ||
            num_sources != (int) PyArray_SIZE(U) ||
            num_sources != (int) PyArray_SIZE(V) ||
            num_sources != (int) PyArray_SIZE(ref) ||
            num_sources != (int) PyArray_SIZE(spix) ||
            num_sources != (int) PyArray_SIZE(rm) ||
            num_sources != (int) PyArray_SIZE(maj) ||
            num_sources != (int) PyArray_SIZE(min) ||
            num_sources != (int) PyArray_SIZE(pa))
    {
        PyErr_SetString(PyExc_RuntimeError, "Input data dimension mismatch.");
        goto fail;
    }

    /* Pointers to input arrays. */
    ra_c = oskar_mem_create_alias_from_raw(PyArray_DATA(ra),
            type, OSKAR_CPU, num_sources, &status);
    dec_c = oskar_mem_create_alias_from_raw(PyArray_DATA(dec),
            type, OSKAR_CPU, num_sources, &status);
    I_c = oskar_mem_create_alias_from_raw(PyArray_DATA(I),
            type, OSKAR_CPU, num_sources, &status);
    Q_c = oskar_mem_create_alias_from_raw(PyArray_DATA(Q),
            type, OSKAR_CPU, num_sources, &status);
    U_c = oskar_mem_create_alias_from_raw(PyArray_DATA(U),
            type, OSKAR_CPU, num_sources, &status);
    V_c = oskar_mem_create_alias_from_raw(PyArray_DATA(V),
            type, OSKAR_CPU, num_sources, &status);
    ref_c = oskar_mem_create_alias_from_raw(PyArray_DATA(ref),
            type, OSKAR_CPU, num_sources, &status);
    spix_c = oskar_mem_create_alias_from_raw(PyArray_DATA(spix),
            type, OSKAR_CPU, num_sources, &status);
    rm_c = oskar_mem_create_alias_from_raw(PyArray_DATA(rm),
            type, OSKAR_CPU, num_sources, &status);
    maj_c = oskar_mem_create_alias_from_raw(PyArray_DATA(maj),
            type, OSKAR_CPU, num_sources, &status);
    min_c = oskar_mem_create_alias_from_raw(PyArray_DATA(min),
            type, OSKAR_CPU, num_sources, &status);
    pa_c = oskar_mem_create_alias_from_raw(PyArray_DATA(pa),
            type, OSKAR_CPU, num_sources, &status);

    /* Copy source data into the sky model. */
    old_num = oskar_sky_num_sources(h);
    oskar_sky_resize(h, old_num + num_sources, &status);
    oskar_mem_copy_contents(oskar_sky_ra_rad(h), ra_c,
            old_num, 0, num_sources, &status);
    oskar_mem_copy_contents(oskar_sky_dec_rad(h), dec_c,
            old_num, 0, num_sources, &status);
    oskar_mem_copy_contents(oskar_sky_I(h), I_c,
            old_num, 0, num_sources, &status);
    oskar_mem_copy_contents(oskar_sky_Q(h), Q_c,
            old_num, 0, num_sources, &status);
    oskar_mem_copy_contents(oskar_sky_U(h), U_c,
            old_num, 0, num_sources, &status);
    oskar_mem_copy_contents(oskar_sky_V(h), V_c,
            old_num, 0, num_sources, &status);
    oskar_mem_copy_contents(oskar_sky_reference_freq_hz(h), ref_c,
            old_num, 0, num_sources, &status);
    oskar_mem_copy_contents(oskar_sky_spectral_index(h), spix_c,
            old_num, 0, num_sources, &status);
    oskar_mem_copy_contents(oskar_sky_rotation_measure_rad(h), rm_c,
            old_num, 0, num_sources, &status);
    oskar_mem_copy_contents(oskar_sky_fwhm_major_rad(h), maj_c,
            old_num, 0, num_sources, &status);
    oskar_mem_copy_contents(oskar_sky_fwhm_minor_rad(h), min_c,
            old_num, 0, num_sources, &status);
    oskar_mem_copy_contents(oskar_sky_position_angle_rad(h), pa_c,
            old_num, 0, num_sources, &status);

    /* Free memory. */
    oskar_mem_free(ra_c, &status);
    oskar_mem_free(dec_c, &status);
    oskar_mem_free(I_c, &status);
    oskar_mem_free(Q_c, &status);
    oskar_mem_free(U_c, &status);
    oskar_mem_free(V_c, &status);
    oskar_mem_free(ref_c, &status);
    oskar_mem_free(spix_c, &status);
    oskar_mem_free(rm_c, &status);
    oskar_mem_free(maj_c, &status);
    oskar_mem_free(min_c, &status);
    oskar_mem_free(pa_c, &status);

    /* Check for errors. */
    if (status)
    {
        PyErr_Format(PyExc_RuntimeError,
                "Sky model append_sources() failed with code %d (%s).",
                status, oskar_get_error_string(status));
        goto fail;
    }

    Py_XDECREF(ra);
    Py_XDECREF(dec);
    Py_XDECREF(I);
    Py_XDECREF(Q);
    Py_XDECREF(U);
    Py_XDECREF(V);
    Py_XDECREF(ref);
    Py_XDECREF(spix);
    Py_XDECREF(rm);
    Py_XDECREF(maj);
    Py_XDECREF(min);
    Py_XDECREF(pa);
    return Py_BuildValue("");

fail:
    Py_XDECREF(ra);
    Py_XDECREF(dec);
    Py_XDECREF(I);
    Py_XDECREF(Q);
    Py_XDECREF(U);
    Py_XDECREF(V);
    Py_XDECREF(ref);
    Py_XDECREF(spix);
    Py_XDECREF(rm);
    Py_XDECREF(maj);
    Py_XDECREF(min);
    Py_XDECREF(pa);
    return 0;
}
void oskar_sky_evaluate_gaussian_source_parameters(oskar_Sky* sky,
        int zero_failed_sources, double ra0, double dec0, int* num_failed,
        int* status)
{
    int i, j, num_sources;
    int type;

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

    /* Return if memory is not on the CPU. */
    if (oskar_sky_mem_location(sky) != OSKAR_CPU)
    {
        *status = OSKAR_ERR_BAD_LOCATION;
        return;
    }

    /* Get data type and number of sources. */
    type = oskar_sky_precision(sky);
    num_sources = oskar_sky_num_sources(sky);

    /* Switch on type. */
    if (type == OSKAR_DOUBLE)
    {
        /* Double precision. */
        const double *ra_, *dec_, *maj_, *min_, *pa_;
        double *I_, *Q_, *U_, *V_, *a_, *b_, *c_;
        double cos_pa_2, sin_pa_2, sin_2pa, inv_std_min_2, inv_std_maj_2;
        double ellipse_a, ellipse_b, maj, min, pa, cos_pa, sin_pa, t;
        double l[ELLIPSE_PTS], m[ELLIPSE_PTS];
        double work1[5 * ELLIPSE_PTS], work2[5 * ELLIPSE_PTS];
        double lon[ELLIPSE_PTS], lat[ELLIPSE_PTS];
        double x[ELLIPSE_PTS], y[ELLIPSE_PTS], z[ELLIPSE_PTS];
        ra_  = oskar_mem_double_const(oskar_sky_ra_rad_const(sky), status);
        dec_ = oskar_mem_double_const(oskar_sky_dec_rad_const(sky), status);
        maj_ = oskar_mem_double_const(oskar_sky_fwhm_major_rad_const(sky), status);
        min_ = oskar_mem_double_const(oskar_sky_fwhm_minor_rad_const(sky), status);
        pa_  = oskar_mem_double_const(oskar_sky_position_angle_rad_const(sky), status);
        I_   = oskar_mem_double(oskar_sky_I(sky), status);
        Q_   = oskar_mem_double(oskar_sky_Q(sky), status);
        U_   = oskar_mem_double(oskar_sky_U(sky), status);
        V_   = oskar_mem_double(oskar_sky_V(sky), status);
        a_   = oskar_mem_double(oskar_sky_gaussian_a(sky), status);
        b_   = oskar_mem_double(oskar_sky_gaussian_b(sky), status);
        c_   = oskar_mem_double(oskar_sky_gaussian_c(sky), status);

        for (i = 0; i < num_sources; ++i)
        {
            /* Note: could do something different from the projection below
             * in the case of a line (i.e. maj or min = 0), as in this case
             * there is no ellipse to project, only two points.
             * -- This continue could then be a if() .. else() instead.
             */
            if (maj_[i] == 0.0 && min_[i] == 0.0) continue;

            /* Evaluate shape of ellipse on the l,m plane. */
            ellipse_a = maj_[i]/2.0;
            ellipse_b = min_[i]/2.0;
            cos_pa = cos(pa_[i]);
            sin_pa = sin(pa_[i]);
            for (j = 0; j < ELLIPSE_PTS; ++j)
            {
                t = j * 60.0 * M_PI / 180.0;
                l[j] = ellipse_a*cos(t)*sin_pa + ellipse_b*sin(t)*cos_pa;
                m[j] = ellipse_a*cos(t)*cos_pa - ellipse_b*sin(t)*sin_pa;
            }
            oskar_convert_relative_directions_to_lon_lat_2d_d(ELLIPSE_PTS,
                    l, m, 0.0, 0.0, lon, lat);

            /* Rotate on the sphere. */
            oskar_convert_lon_lat_to_xyz_d(ELLIPSE_PTS, lon, lat, x, y, z);
            oskar_rotate_sph_d(ELLIPSE_PTS, x, y, z, ra_[i], dec_[i]);
            oskar_convert_xyz_to_lon_lat_d(ELLIPSE_PTS, x, y, z, lon, lat);

            oskar_convert_lon_lat_to_relative_directions_2d_d(
                    ELLIPSE_PTS, lon, lat, ra0, dec0, l, m);

            /* Get new major and minor axes and position angle. */
            oskar_fit_ellipse_d(&maj, &min, &pa, ELLIPSE_PTS, l, m, work1,
                    work2, status);

            /* Check if fitting failed. */
            if (*status == OSKAR_ERR_ELLIPSE_FIT_FAILED)
            {
                if (zero_failed_sources)
                {
                    I_[i] = 0.0;
                    Q_[i] = 0.0;
                    U_[i] = 0.0;
                    V_[i] = 0.0;
                }
                ++(*num_failed);
                *status = 0;
                continue;
            }
            else if (*status) break;

            /* Evaluate ellipse parameters. */
            inv_std_maj_2 = 0.5 * (maj * maj) * M_PI_2_2_LN_2;
            inv_std_min_2 = 0.5 * (min * min) * M_PI_2_2_LN_2;
            cos_pa_2 = cos(pa) * cos(pa);
            sin_pa_2 = sin(pa) * sin(pa);
            sin_2pa  = sin(2.0 * pa);
            a_[i] = cos_pa_2*inv_std_min_2     + sin_pa_2*inv_std_maj_2;
            b_[i] = -sin_2pa*inv_std_min_2*0.5 + sin_2pa *inv_std_maj_2*0.5;
            c_[i] = sin_pa_2*inv_std_min_2     + cos_pa_2*inv_std_maj_2;
        }
    }
    else
    {
        /* Single precision. */
        const float *ra_, *dec_, *maj_, *min_, *pa_;
        float *I_, *Q_, *U_, *V_, *a_, *b_, *c_;
        float cos_pa_2, sin_pa_2, sin_2pa, inv_std_min_2, inv_std_maj_2;
        float ellipse_a, ellipse_b, maj, min, pa, cos_pa, sin_pa, t;
        float l[ELLIPSE_PTS], m[ELLIPSE_PTS];
        float work1[5 * ELLIPSE_PTS], work2[5 * ELLIPSE_PTS];
        float lon[ELLIPSE_PTS], lat[ELLIPSE_PTS];
        float x[ELLIPSE_PTS], y[ELLIPSE_PTS], z[ELLIPSE_PTS];
        ra_  = oskar_mem_float_const(oskar_sky_ra_rad_const(sky), status);
        dec_ = oskar_mem_float_const(oskar_sky_dec_rad_const(sky), status);
        maj_ = oskar_mem_float_const(oskar_sky_fwhm_major_rad_const(sky), status);
        min_ = oskar_mem_float_const(oskar_sky_fwhm_minor_rad_const(sky), status);
        pa_  = oskar_mem_float_const(oskar_sky_position_angle_rad_const(sky), status);
        I_   = oskar_mem_float(oskar_sky_I(sky), status);
        Q_   = oskar_mem_float(oskar_sky_Q(sky), status);
        U_   = oskar_mem_float(oskar_sky_U(sky), status);
        V_   = oskar_mem_float(oskar_sky_V(sky), status);
        a_   = oskar_mem_float(oskar_sky_gaussian_a(sky), status);
        b_   = oskar_mem_float(oskar_sky_gaussian_b(sky), status);
        c_   = oskar_mem_float(oskar_sky_gaussian_c(sky), status);

        for (i = 0; i < num_sources; ++i)
        {
            /* Note: could do something different from the projection below
             * in the case of a line (i.e. maj or min = 0), as in this case
             * there is no ellipse to project, only two points.
             * -- This continue could then be a if() .. else() instead.
             */
            if (maj_[i] == 0.0 && min_[i] == 0.0) continue;

            /* Evaluate shape of ellipse on the l,m plane. */
            ellipse_a = maj_[i]/2.0;
            ellipse_b = min_[i]/2.0;
            cos_pa = cos(pa_[i]);
            sin_pa = sin(pa_[i]);
            for (j = 0; j < ELLIPSE_PTS; ++j)
            {
                t = j * 60.0 * M_PI / 180.0;
                l[j] = ellipse_a*cos(t)*sin_pa + ellipse_b*sin(t)*cos_pa;
                m[j] = ellipse_a*cos(t)*cos_pa - ellipse_b*sin(t)*sin_pa;
            }
            oskar_convert_relative_directions_to_lon_lat_2d_f(ELLIPSE_PTS,
                    l, m, 0.0, 0.0, lon, lat);

            /* Rotate on the sphere. */
            oskar_convert_lon_lat_to_xyz_f(ELLIPSE_PTS, lon, lat, x, y, z);
            oskar_rotate_sph_f(ELLIPSE_PTS, x, y, z, ra_[i], dec_[i]);
            oskar_convert_xyz_to_lon_lat_f(ELLIPSE_PTS, x, y, z, lon, lat);

            oskar_convert_lon_lat_to_relative_directions_2d_f(
                    ELLIPSE_PTS, lon, lat, (float)ra0, (float)dec0, l, m);

            /* Get new major and minor axes and position angle. */
            oskar_fit_ellipse_f(&maj, &min, &pa, ELLIPSE_PTS, l, m, work1,
                    work2, status);

            /* Check if fitting failed. */
            if (*status == OSKAR_ERR_ELLIPSE_FIT_FAILED)
            {
                if (zero_failed_sources)
                {
                    I_[i] = 0.0;
                    Q_[i] = 0.0;
                    U_[i] = 0.0;
                    V_[i] = 0.0;
                }
                ++(*num_failed);
                *status = 0;
                continue;
            }
            else if (*status) break;

            /* Evaluate ellipse parameters. */
            inv_std_maj_2 = 0.5 * (maj * maj) * M_PI_2_2_LN_2;
            inv_std_min_2 = 0.5 * (min * min) * M_PI_2_2_LN_2;
            cos_pa_2 = cos(pa) * cos(pa);
            sin_pa_2 = sin(pa) * sin(pa);
            sin_2pa  = sin(2.0 * pa);
            a_[i] = cos_pa_2*inv_std_min_2     + sin_pa_2*inv_std_maj_2;
            b_[i] = -sin_2pa*inv_std_min_2*0.5 + sin_2pa *inv_std_maj_2*0.5;
            c_[i] = sin_pa_2*inv_std_min_2     + cos_pa_2*inv_std_maj_2;
        }
    }
}
Example #16
0
oskar_Sky* oskar_sky_load(const char* filename, int type, int* status)
{
    int n = 0;
    FILE* file;
    char* line = 0;
    size_t bufsize = 0;
    oskar_Sky* sky;

    /* Check if safe to proceed. */
    if (*status) return 0;

    /* Get the data type. */
    if (type != OSKAR_SINGLE && type != OSKAR_DOUBLE)
    {
        *status = OSKAR_ERR_BAD_DATA_TYPE;
        return 0;
    }

    /* Open the file. */
    file = fopen(filename, "r");
    if (!file)
    {
        *status = OSKAR_ERR_FILE_IO;
        return 0;
    }

    /* Initialise the sky model. */
    sky = oskar_sky_create(type, OSKAR_CPU, 0, status);

    /* Loop over lines in file. */
    while (oskar_getline(&line, &bufsize, file) != OSKAR_ERR_EOF)
    {
        /* Set defaults. */
        /* RA, Dec, I, Q, U, V, freq0, spix, RM, FWHM maj, FWHM min, PA */
        double par[] = {0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0., 0.};
        size_t num_param = sizeof(par) / sizeof(double);
        size_t num_required = 3, num_read = 0;

        /* Load source parameters (require at least RA, Dec, Stokes I). */
        num_read = oskar_string_to_array_d(line, num_param, par);
        if (num_read < num_required)
            continue;

        /* Ensure enough space in arrays. */
        if (oskar_sky_num_sources(sky) <= n)
        {
            oskar_sky_resize(sky, n + 100, status);
            if (*status)
                break;
        }

        if (num_read <= 9)
        {
            /* RA, Dec, I, Q, U, V, freq0, spix, RM */
            oskar_sky_set_source(sky, n, par[0] * deg2rad,
                    par[1] * deg2rad, par[2], par[3], par[4], par[5],
                    par[6], par[7], par[8], 0.0, 0.0, 0.0, status);
        }
        else if (num_read == 11)
        {
            /* Old format, with no rotation measure. */
            /* RA, Dec, I, Q, U, V, freq0, spix, FWHM maj, FWHM min, PA */
            oskar_sky_set_source(sky, n, par[0] * deg2rad,
                    par[1] * deg2rad, par[2], par[3], par[4], par[5],
                    par[6], par[7], 0.0, par[8] * arcsec2rad,
                    par[9] * arcsec2rad, par[10] * deg2rad, status);
        }
        else if (num_read == 12)
        {
            /* New format. */
            /* RA, Dec, I, Q, U, V, freq0, spix, RM, FWHM maj, FWHM min, PA */
            oskar_sky_set_source(sky, n, par[0] * deg2rad,
                    par[1] * deg2rad, par[2], par[3], par[4], par[5],
                    par[6], par[7], par[8], par[9] * arcsec2rad,
                    par[10] * arcsec2rad, par[11] * deg2rad, status);
        }
        else
        {
            /* Error. */
            *status = OSKAR_ERR_BAD_SKY_FILE;
            break;
        }
        ++n;
    }

    /* Set the size to be the actual number of elements loaded. */
    oskar_sky_resize(sky, n, status);

    /* Free the line buffer and close the file. */
    if (line) free(line);
    fclose(file);

    /* Check if an error occurred. */
    if (*status)
    {
        oskar_sky_free(sky, status);
        sky = 0;
    }

    /* Return a handle to the sky model. */
    return sky;
}
void oskar_sky_append_to_set(int* set_size, oskar_Sky*** set_ptr,
        int max_sources_per_model, const oskar_Sky* model, int* status)
{
    int free_space, space_required, num_extra_models, number_to_copy;
    int i, j, type, location, from_offset;
    oskar_Sky **set;
    size_t new_size;

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

    /* Get type and location. */
    type     = oskar_sky_precision(model);
    location = oskar_sky_mem_location(model);
    if (location != OSKAR_CPU)
    {
        *status = OSKAR_ERR_BAD_LOCATION;
        return;
    }

    /* Work out if the set needs to be resized, and if so by how much. */
    free_space = (*set_size == 0) ? 0 :
            max_sources_per_model - (*set_ptr)[*set_size - 1]->num_sources;
    space_required = model->num_sources - free_space;
    num_extra_models = (space_required + max_sources_per_model - 1)
            / max_sources_per_model;

    /* Sanity check. */
    if (num_extra_models < 0)
    {
        *status = OSKAR_ERR_INVALID_ARGUMENT;
        return;
    }

    /* Resize the array of sky model handles. */
    new_size = (*set_size + num_extra_models) * sizeof(oskar_Sky*);
    *set_ptr = realloc((*set_ptr), new_size);
    set = *set_ptr;
    for (i = *set_size; i < *set_size + num_extra_models; ++i)
    {
        set[i] = oskar_sky_create(type, location,
                max_sources_per_model, status);
        /* TODO Please clarify this statement and explain why it's needed. */
        /* Set the number sources to zero as this is the number currently
         * allocated in the model. */
        set[i]->num_sources = 0;
    }

    if (*status) return;

    /* Copy sources from the model into the set. */
    /* Loop over set entries with free space and copy sources into them. */
    number_to_copy = model->num_sources;
    from_offset = 0;
    for (i = (*set_size-1 > 0) ? *set_size-1 : 0;
            i < *set_size + num_extra_models; ++i)
    {
        int n_copy, offset_dst;
        offset_dst = oskar_sky_num_sources(set[i]);
        free_space = max_sources_per_model - offset_dst;
        n_copy = MIN(free_space, number_to_copy);
        oskar_sky_copy_contents(set[i], model, offset_dst, from_offset,
                n_copy, status);
        if (*status) break;
        set[i]->num_sources = n_copy + offset_dst;
        number_to_copy     -= n_copy;
        from_offset        += n_copy;
    }

    if (*status) return;

    /* Set the use extended flag if needed. */
    for (j = (*set_size-1 > 0) ? *set_size-1 : 0;
            j < *set_size + num_extra_models; ++j)
    {
        oskar_Sky* sky = set[j];
        const oskar_Mem *major, *minor;

        /* If any source in the model is extended, set the flag. */
        major = oskar_sky_fwhm_major_rad_const(sky);
        minor = oskar_sky_fwhm_minor_rad_const(sky);
        if (type == OSKAR_DOUBLE)
        {
            const double *maj_, *min_;
            maj_ = oskar_mem_double_const(major, status);
            min_ = oskar_mem_double_const(minor, status);
            for (i = 0; i < sky->num_sources; ++i)
            {
                if (maj_[i] > 0.0 || min_[i] > 0.0)
                {
                    sky->use_extended = OSKAR_TRUE;
                    break;
                }
            }
        }
        else
        {
            const float *maj_, *min_;
            maj_ = oskar_mem_float_const(major, status);
            min_ = oskar_mem_float_const(minor, status);
            for (i = 0; i < sky->num_sources; ++i)
            {
                if (maj_[i] > 0.0 || min_[i] > 0.0)
                {
                    sky->use_extended = OSKAR_TRUE;
                    break;
                }
            }
        }
    }

    /* Update the set size */
    *set_size += num_extra_models;
}