Class ZarrLeapDataset

Inheritance Relationships

Base Type

Class Documentation

class ZarrLeapDataset : public ska::LeapDataset

An abstraction layer around a Zarr MSv4 MeasurementSet that provides all data required for leap calibration. This class additionally stores runtime user specificed variables and cached variabled calculated from the underlying measurement set.

Public Functions

ZarrLeapDataset(const std::string &filepath)

Construct a new Zarr Leap Dataset object.

Parameters:

filepath – a Casa MeasurementSet v4 filepath

virtual std::optional<std::string> GetFilepath() const override

Get the file path of the data.

virtual uint32_t GetTotalAntennas() const override

Get the total number of antennas including flagged antennas.

virtual uint32_t GetNumStations() const override

Get the number of stations excluding flagged stations.

Returns:

uint32_t

virtual uint32_t GetNumBaselines() const override

Get the number of baselines in the measurement set using the current autocorrelations setting and including stations not recording rows.

Note

TODO: baselines should always be n*(n-1) / 2 and without autocorrelations

Returns:

uint32_t

virtual uint32_t GetNumPols() const override

Get the number of polarizations in the measurement set.

Returns:

uint32_t

virtual uint32_t GetNumChannels() const override

Get the number of channels in the measurement set.

Returns:

uint32_t

virtual double GetFreqStartHz() const override
virtual double GetFreqIncHz() const override
virtual Eigen::Vector2d GetPhaseCentreRad() const override
virtual uint32_t GetNumRows() const override

Get the number of rows in the measurement set (non-flagged baselines * timesteps).

Returns:

uint32_t

std::vector<std::u32string> GetAntennaNames() const
std::vector<std::u32string> GetAntenna1Names() const
std::vector<std::u32string> GetAntenna2Names() const
virtual Eigen::VectorXi GetAntenna1() const override

Get the indexes of the first antenna in baselines.

Returns:

Eigen::VectorXi

virtual Eigen::VectorXi GetAntenna2() const override

Get the indexes of the second antenna in baselines.

Returns:

Eigen::VectorXi

virtual uint32_t GetNumTimesteps() const override

Get the total number of timesteps in the measurement set.

Returns:

uint32_t

virtual std::vector<double> GetVisibilityTimeIntervals() const override

Get the time interval of visibilities in seconds.

virtual std::vector<double> GetVisibilityTimestamps() const override

Get Time coordinates of visibilities in seconds from MJD epoch.

Note

Visibility timestamps are the mid-point of the correlated period (not the centroid).

Returns:

std::vector<double>

virtual Eigen::VectorXb GetFlaggedBaselines() const override

Get a vector of size nBaselines with a true value at the index of unflagged baselines. Flag is is logical and of channels and polarizations.

Returns:

Eigen::VectorXb

virtual uint32_t GetNumFlaggedBaselines() const override

Get the number of baselines that are flagged by the measurement set.

Returns:

uint32_t

virtual Eigen::VectorXb GetShortBaselines(double minimumBaselineThreshold = 0.0) const override

Get a flag vector of short baselines.

Parameters:

minimumBaselineThreshold – baseline threshold

Returns:

Eigen::VectorXb

virtual uint32_t GetNumShortBaselines(double minimumBaselineThreshold = 0.0) const override

Get the number of baselines that below the minimumBaselineThreshold.

Parameters:

minimumBaselineThreshold – baseline threshold

Returns:

uint32_t

virtual Eigen::VectorXb GetFilteredBaselines(double minimumBaselineThreshold = 0.0) const override

Get flag vector of filtered baselines that are either flagged or short.

Parameters:

minimumBaselineThreshold – baseline threshold

Returns:

Eigen::VectorXb

virtual uint32_t GetNumFilteredBaselines(double minimumBaselineThreshold = 0.0) const override

Get the number of baselines that are flagged baselines or short baselines.

Parameters:

minimumBaselineThreshold – baseline threshold

Returns:

uint32_t

virtual Eigen::Tensor<double, 3> ReadCoords() const override

Reads UVW coordinates from the measurement set TODO: rename ReadUVWs.

Returns:

Eigen::Tensor<double, 3>

virtual Eigen::Tensor<double, 3> ReadCoords(const Slice &timestepSlice) const override

Get the Coords/UVWs of a specified time interval.

Parameters:

  • startTimestep –

  • intervalTimesteps –

Returns:

Eigen::Tensor<double, 3> of dimensions (3, baselines, timesteps)

virtual Eigen::Tensor<double, 3> ReadCoords(uint32_t startTimestep, uint32_t intervalTimesteps) const override

Get the Coords/UVWs of a specified time interval.

Parameters:

  • startTimestep –

  • intervalTimesteps –

Returns:

Eigen::Tensor<double, 3> of dimensions (3, baselines, timesteps)

virtual Eigen::Tensor<std::complex<double>, 4> ReadVis() const override

Get the visibilities from all baselines, channels and polarizations for the first timestep.

Returns:

Eigen::Tensor<std::complex<double>, 4> of dimensions (polarizations, channels, baselines, timesteps)

virtual Eigen::Tensor<std::complex<double>, 4> ReadVis(const Slice &timestepSlice, const Slice &polarizationSlice = Slice(0, std::nullopt, 1)) const override

Get visibilities from the specificed dimension slices of a specified timestep slice.

Parameters:

  • startTimestep – start timestep index

  • intervalTimesteps – number of timesteps

Returns:

Eigen::Tensor<std::complex<double>, 4> of dimensions (polarizations, channels, baselines, timesteps)

virtual Eigen::Tensor<std::complex<double>, 4> ReadVis(std::uint32_t startTimestep, std::uint32_t intervalTimesteps, const Slice &polarizationSlice = Slice(0, std::nullopt, 1)) const override

Get visibilities from the specificed dimension slices of a specified timestep slice.

Parameters:

  • startTimestep – start timestep index

  • intervalTimesteps – number of timesteps

Returns:

Eigen::Tensor<std::complex<double>, 4> of dimensions (polarizations, channels, baselines, timesteps)

virtual Eigen::Tensor<std::complex<double>, 4> ReadVis(uint32_t startTimestep, uint32_t intervalTimesteps, Range<int32_t> polarizationRange, const char *column) const override

Reads from file visibilities using specified dimension slices.

Parameters:

  • startTimestep –

  • intervalTimesteps –

  • polarizationRange –

  • column –

Returns:

Eigen::Tensor<std::complex<double>, 4> of dimensions (polarizations, channels, baselines, timesteps)

virtual std::set<int32_t> GetFlaggedAntennas() const override

Get the antenna indexes that are either not present in any baselines or are flagged in all of it’s baselines.

Indexes are out of the total antennas.

Testing only.

Returns:

std::set<int32_t>