orca.flagging.flagoperations

Low-level flag manipulation operations for measurement sets.

Provides functions for directly manipulating FLAG columns in CASA measurement sets, including flagging antennas, baselines, merging flags between observations, and I/O with numpy arrays.

Originally adapted from Marin Anderson’s code (3/8/2019).

Functions

flag_ants: Flag all visibilities involving specified antennas.
merge_flags: OR-merge flags between two measurement sets.
merge_group_flags: OR-merge flags across a group of measurement sets.
write_to_flag_column: Apply flags from a numpy array to a measurement set.
save_to_flag_npy: Save the FLAG column to a numpy file.
flag_bls: Apply baseline flags from a text file.

Attributes

`DATA`
`CORRECTED_DATA`

Functions

`flag_ants`(→ str)	Flag all visibilities involving specified antennas.
`merge_flags`(→ Tuple[str, str])	OR-merge flags between two measurement sets.
`merge_group_flags`(→ List[str])	OR-merge flags across a group of measurement sets.
`write_to_flag_column`(→ str)	Apply flags from a numpy array to a measurement set.
`save_to_flag_npy`(→ str)	Save the FLAG column from a measurement set to a numpy file.
`flag_bls`(→ str)	Apply baseline flags from a text file to a measurement set.

Module Contents

orca.flagging.flagoperations.DATA = 'DATA'[source]

orca.flagging.flagoperations.CORRECTED_DATA = 'CORRECTED_DATA'[source]

orca.flagging.flagoperations.flag_ants(ms: str, ants: List[int]) → str[source]

Flag all visibilities involving specified antennas.

Parameters:

ms – Path to the measurement set.
ants – List of antenna indices (0-indexed) to flag.

Returns:

Path to the modified measurement set.

orca.flagging.flagoperations.merge_flags(ms1: str, ms2: str) → Tuple[str, str][source]

OR-merge flags between two measurement sets.

Updates both measurement sets so their FLAG columns contain the logical OR of the original flags from both files.

Parameters:

ms1 – Path to the first measurement set.
ms2 – Path to the second measurement set.

Returns:

Tuple of (ms1, ms2) paths.

orca.flagging.flagoperations.merge_group_flags(ms_list: List[str]) → List[str][source]

OR-merge flags across a group of measurement sets.

Updates all measurement sets so they share the same merged FLAG column, containing the logical OR of flags from all input files.

Parameters:: ms_list – List of measurement set paths.
Returns:: The input list of paths (all now updated).

orca.flagging.flagoperations.write_to_flag_column(ms: str, flag_npy: str) → str[source]

Apply flags from a numpy array to a measurement set.

The numpy array is OR-merged with existing flags.

Parameters:

ms – Path to the measurement set.
flag_npy – Path to the numpy file containing boolean flag array.

Returns:

Path to the modified measurement set.

Raises:

AssertionError – If the flag array shape doesn’t match the MS.

orca.flagging.flagoperations.save_to_flag_npy(ms: str, flag_npy: str) → str[source]

Save the FLAG column from a measurement set to a numpy file.

Parameters:

ms – Path to the measurement set.
flag_npy – Output path for the numpy file.

Returns:

Path to the saved numpy file.

orca.flagging.flagoperations.flag_bls(msfile: str, blfile: str) → str[source]

Apply baseline flags from a text file to a measurement set.

Parameters:

msfile – Path to the measurement set.
blfile – Path to the baseline flag file. Format is one baseline per line as ‘ant1&ant2’ (0-indexed).

Returns:

Path to the modified measurement set.

Raises:

ValueError – If the number of visibilities is unexpected.