calculate_visibilities_common

API documentation for calculate_visibilities_common.c

Functions

void calculate_component_visis(e_component_type comptype, calc_visi_inouts_t *mem_calc_visi_inouts, double *cpu_channel_freqs, woden_settings_t *woden_settings, beam_settings_t *beam_settings, source_t *source, source_t *mem_chunked_source, visibility_set_t *mem_visibility_set, int num_beams, int use_twobeams, int do_gpu)

Calculate the visibilities for a given component type, on either the CPU or GPU, for a single chunk of the sky model.

This function computes primary beam reponses and calculates the visibilities for a specified component type (POINT, GAUSSIAN, or SHAPELET) using the provided input and output structures, frequency channels, and settings. Any input with mem_ prefix needs to be allocated on the GPU if do_gpu is set to 1. Otherwise it should be allocated on the CPU.

Because EveryBeam only works on the CPU, even when running in GPU mode, need access to the CPU version of the source, hence we have to input source and mem_chunked_source separately. Stops multiple GPU copying doing the copy in mem_chunked_source outside of this function.

Parameters:

  • comptype – The type of component for which to calculate visibilities.

  • mem_calc_visi_inouts – Pointer to the structure containing input and output data for visibility calculation.

  • cpu_channel_freqs – Pointer to the array of frequency channels.

  • woden_settings – Pointer to the WODEN settings structure.

  • beam_settings – Pointer to the beam settings structure.

  • source – Pointer to the source structure.

  • mem_chunked_source – Pointer to the chunked source structure.

  • mem_visibility_set – Pointer to the visibility set structure.

  • num_beams – The number of beams to be used in the calculation.

  • use_twobeams – Flag indicating whether to use two beams (1) or not (0). This means use two different beams per baseline, so assumes a unique beam for each station.

  • do_gpu – Flag indicating whether to perform the calculation on the GPU (1) or CPU (0).

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)

Calculates the visibilities for a given array layout and source catalogue.

This function computes the visibilities based on the provided array layout, cropped sky models, beam settings, and WODEN settings. The results are stored in the visibility set.

woden_settings contains settings indicating what kind of simulation is to be run. cropped_sky_models contains the sky model, chunked into pieces that should fit on the CPU/GPU. array_layout hold the array layout, and sbf holds the shapelet basis functions. beam_settings holds the primary some primary beam settings, and initialised hyperbeam objects. visibility_set should be an array of visibility_set_t structs, one for each coarse band. All should be fully initialised before calling this function.

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->sources

  • beam_settings->beamtype

  • 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->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

for all visibility_set in visibility_sets. Beyond that, depending on your settings, other attributes may be required.

Parameters:

  • array_layout – Pointer to the array layout structure.

  • cropped_sky_models – Pointer to the cropped sky models structure.

  • beam_settings – Pointer to the beam settings structure.

  • woden_settings – Pointer to the WODEN settings structure.

  • visibility_set – Pointer to the visibility set structure where results will be stored.

  • sbf – Pointer to the shapelet basis functions array

calc_visi_inouts_t *create_calc_visi_inouts_gpu(array_layout_t *array_layout, visibility_set_t *visibility_set, visibility_set_t *d_visibility_set, user_precision_t *sbf, woden_settings_t *woden_settings, int num_shapelets, int use_twobeams)

External GPU code linked in from calculate_visibilities_gpu.c, see calculate_visibilities_gpu.h for full details.

void set_visibilities_to_zero_gpu(visibility_set_t *d_visibility_set, visibility_set_t *chunk_visibility_set, int num_visis)

External GPU code linked in from calculate_visibilities_gpu.c, see calculate_visibilities_gpu.h for full details.

void copy_gpu_visi_set_to_host(visibility_set_t *d_visibility_set, calc_visi_inouts_t *d_calc_visi_inouts, visibility_set_t *chunk_visibility_set, int num_visis)

External GPU code linked in from calculate_visibilities_gpu.c, see calculate_visibilities_gpu.h for full details.

void free_calc_visi_inouts_gpu(calc_visi_inouts_t *d_calc_visi_inouts, visibility_set_t *d_visibility_set, int num_shapelets, int use_twobeams)

External GPU code linked in from calculate_visibilities_gpu.c, see calculate_visibilities_gpu.h for full details.

source_t *copy_chunked_source_to_GPU(source_t *chunked_source)

External GPU code linked in from source_components_gpu.cpp, see source_components_gpu.h for full details.

void free_extrapolated_flux_arrays_gpu(components_t *d_components)

External GPU code linked in from source_components_gpu.cpp, see source_components_gpu.h for full details.

void free_components_gpu(source_t *d_chunked_source, e_component_type comptype)

External GPU code linked in from source_components_gpu.cpp, see source_components_gpu.h for full details.

void free_beam_gains_gpu(beam_gains_t *d_beam_gains, e_beamtype beamtype)

External GPU code linked in from source_components_gpu.cpp, see source_components_gpu.h for full details.

void calc_visi_point_or_gauss_gpu(components_t d_components, beam_gains_t d_component_beam_gains, calc_visi_inouts_t *d_calc_visi_inouts, visibility_set_t *d_visibility_set, int num_components, e_beamtype beamtype, e_component_type comptype, woden_settings_t *woden_settings)

External GPU code linked in from source_components_gpu.cpp, see source_components_gpu.h for full details.

void calc_visi_shapelets_gpu(components_t d_components, beam_gains_t d_component_beam_gains, calc_visi_inouts_t *d_calc_visi_inouts, visibility_set_t *d_visibility_set, int num_shapes, int num_shape_coeffs, e_beamtype beamtype, woden_settings_t *woden_settings)

External GPU code linked in from source_components_gpu.cpp, see source_components_gpu.h for full details.

void calc_uvw_gpu(double *d_X_diff, double *d_Y_diff, double *d_Z_diff, user_precision_t *d_u_metres, user_precision_t *d_v_metres, user_precision_t *d_w_metres, user_precision_t *d_us, user_precision_t *d_vs, user_precision_t *d_ws, user_precision_t *d_allsteps_wavelengths, double *d_allsteps_cha0s, double *d_allsteps_sha0s, woden_settings_t *woden_settings)

External GPU code linked in from fundamental_coords_gpu.cpp, see fundamental_coords_gpu.h for full details.

void calc_uv_shapelet_gpu(user_precision_t *d_u_shapes, user_precision_t *d_v_shapes, int num_shapes, double *d_X_diff, double *d_Y_diff, double *d_Z_diff, double *d_ras, double *d_decs, woden_settings_t *woden_settings)

External GPU code linked in from fundamental_coords_gpu.cpp, see fundamental_coords_gpu.h for full details.

void set_auto_uvw_to_zero_gpu(int num_cross, int num_autos, user_precision_t *d_u, user_precision_t *d_v, user_precision_t *d_w)

External GPU code linked in from fundamental_coords_gpu.cpp, see fundamental_coords_gpu.h for full details.