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#ifndef WSCLEAN_INTERFACE_IN_MEMORY_MS_H_
#define WSCLEAN_INTERFACE_IN_MEMORY_MS_H_
#include <array>
#include <complex>
#include <cstdint>
#include <string>
#include <vector>
#include <aocommon/multibanddata.h>
#include <aocommon/polarization.h>
namespace wsclean {
/**
* Single row of data, including meta data. Comparable to a row in a measurement
* set. A row contains the data for one baseline, one timestep.
*/
struct InMemoryRow {
/**
* Flattened data array of size polarizations x frequencies, where
* polarization is the fastest changing. The number of polarizations should
* match with the length of InMemoryMs::polarizations. The number of channels
* must match with the number of channels in InMemoryMs::bands[data_desc_id].
* The number of channels may be variable, e.g. when baseline-dependent
* averaging is used or when the observations covers multiple bands with
* different channel counts.
*/
std::vector<std::complex<float>> data;
/**
* Weights associated with the @c data values, with the same shape. For
* flagged values, the weight should be set to zero.
*/
std::vector<float> weights;
std::array<double, 3> uvw{0.0, 0.0, 0.0};
double time = 0.0;
uint32_t data_desc_id = 0;
uint32_t field_id = 0;
uint32_t antenna1 = 0;
uint32_t antenna2 = 0;
};
/**
* An InMemoryMs is a memory buffer for the data for a measurement set. It
* contains only the data that is relevant for WSClean, being the observed
* visibility data and some of the meta data required for imaging.
*/
struct InMemoryMs {
/**
* Each row contain the data for one baseline, one timestep, with all channels
* and all polarizations.
*/
std::vector<InMemoryRow> rows;
/**
* Righ ascension in radians.
*/
double phase_centre_ra = 0.0;
/**
* Declination in radians.
*/
double phase_centre_dec = 0.0;
/**
* Bands that are used. The InMemoryRow::data_desc_id are indices into this
* structure.
*/
aocommon::MultiBandData bands;
/**
* Antenna names are currently only used when solutions are applied, to link
* data in the h5 solution files to the right antennas. Note that the concept
* of an "antenna" here is the same as an antenna in a measurement set. For
* e.g. LOFAR, a station is an antenna. InMemoryRow::antenna1 and 2 are
* indices into this structure.
*/
std::vector<std::string> antenna_names;
/**
* List of polarizations in the data, e.g. {XX, XY, YX, YY}.
*/
std::vector<aocommon::PolarizationEnum> polarizations;
/**
* Should be set to true when InMemoryRow::data_desc_id is used to distinguish
* different averaging factors for frequency-direction baseline-dependent
* averaging.
*/
bool has_frequency_bda = false;
/**
* Could be in the future used as diagnostic; currently not used. Time BDA is
* supported even if set to false.
*/
bool has_time_bda = false;
/**
* Copied to output FITS files, e.g. "LOFAR" or "JVLA".
*/
std::string telescope_name;
/**
* Copied to output FITS files, e.g. "M. Veldhuis".
*/
std::string observer;
/**
* Copied to output FITS files, e.g. "3C196" or "LOTSS P113+24".
*/
std::string field_name;
/**
* Copied to output FITS files, time in MJD seconds.
*/
double start_time = 0.0;
/**
* Number of seconds between adjacent timesteps. Only relevant when
* no time-direction baseline-dependent averaging is used. It is
* used for determining time-smearing (only when explicitly enabled).
*/
double interval = 0.0;
};
} // namespace wsclean
#endif
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