calculate_visibilities

API documentation for calculate_visibilities.cu

Primary function to take the simulation settings and sky models generated on the host, transfer everything over to the device, run the simulation through the CUDA code, and grab everything back off the device and onto the host.

Author

J.L.B. Line

Functions

void calculate_visibilities(array_layout_t *array_layout, source_catalogue_t *cropped_sky_models, beam_settings_t *beam_settings, woden_settings_t *woden_settings, visibility_set_t *visibility_set, user_precision_t *sbf)

Given the telescope, settings, and sky models detailed in array_layout, cropped_sky_models, and woden_settings, run the GPU simulation, and store the output visibilities in visibility_set

Uses the telescope model described in array_layout, an array of sky models and beam settings described by cropped_sky_models, the primary beam settings described by beam_settings and the simulation settings described in woden_settings to run the GPU simulation. sbf is the shapelet basis function, which will be copied in device memory if SHAPELET components are present in the sky models. num_chunks corresponds to the length of the cropped_sky_models array. The function will run each sky model in cropped_sky_models as a separate simulation, and sum the resultant visibilities into visibility_set.

Parameters:

• *array_layout – [in] Pointer to an array_layout_t struct

• *cropped_sky_models – [in] Pointer to a populated source_catalogue_t struct

• *beam_settings – [in] Pointer to populated beam_settings_t struct

• *woden_settings – [in] Pointer to a populated woden_settings_t struct

• *visibility_set – [inout] Pointer to an initialised visibility_set_t struct

• *sbf – [in] An array of gridded shapelet basis function values as created by create_sbf

    NOTE
  
    The following attributes *must* be set for `calculate_visibilities` to work:
  
    array_layout->X_diff_metres
    array_layout->Y_diff_metres
    array_layout->Z_diff_metres
    cropped_sky_models->num_sources
    cropped_sky_models->catsources
    cropped_sky_models->beam_settings
    woden_settings->num_baselines
    woden_settings->num_time_steps
    woden_settings->num_visis
    woden_settings->num_freqs
    woden_settings->beamtype
    woden_settings->ra0
    woden_settings->sdec0
    woden_settings->cdec0
    visibility_set->allsteps_cha0s
    visibility_set->allsteps_sha0s
    visibility_set->allsteps_lsts
    visibility_set->allsteps_wavelengths
    visibility_set->channel_frequencies
  
    The following must be malloc-ed for `calculate_visibilities` to work:
  
    visibility_set->sum_visi_real
    visibility_set->sum_visi_imag
    visibility_set->us_metres
    visibility_set->vs_metres
    visibility_set->ws_metres
    visibility_set->sum_visi_XX_real
    visibility_set->sum_visi_XX_imag
    visibility_set->sum_visi_XY_real
    visibility_set->sum_visi_XY_imag
    visibility_set->sum_visi_YX_real
    visibility_set->sum_visi_YX_imag
    visibility_set->sum_visi_YY_real
    visibility_set->sum_visi_YY_imag
  
    Beyond that, depending on your primary beam settings,
    other attributes may be required.