ngEHT conversion guide

from importlib.metadata import version
import os

try:
    import xradio

    print("XRADIO version", version("xradio"), "already installed.")
except ImportError as e:
    print(e)
    print("Installing XRADIO")

    os.system("pip install xradio")

    import xradio

    print("xradio version", version("xradio"), " installed.")

XRADIO version 1.1.3 already installed.

Download dataset

fitsidi from https://almascience.eso.org/almadata/ec/eht/2016.1.01114.V/group.uid___A001_X87c_X245.ec_jlgomez.e17a10-7-hi-oj287-3C279-fits.tgz

importfitsidi('E17A10.0.bin0000.source0000.FITS',vis='E17A10.0.bin0000.source0000.ms')
mstransform(vis='E17A10.0.bin0000.source0000.ms',outputvis='ngEHT_E17A10.0.bin0000.source0000_split_lsrk.ms',spw='8:55~61,29:20~27', regridms=True,outframe='lsrk',datacolumn='all')

import toolviper

toolviper.utils.data.download(file="ngEHT_E17A10.0.bin0000.source0000_split.ms")

[2026-04-20 15:19:36,129]     INFO   toolviper:  Initializing download...
[2026-04-20 15:19:36,130]     INFO   toolviper:  File already exists: /Users/vdesouza/work/xradio/docs/source/measurement_set/guides/ngEHT_E17A10.0.bin0000.source0000_split.ms

Convert to Processing Set

from xradio.measurement_set import convert_msv2_to_processing_set

ms_file = "ngEHT_E17A10.0.bin0000.source0000_split.ms"

main_chunksize = {"frequency": 1, "time": 20}  # baseline, polarization
outfile = "ngEHT_E17A10.0.bin0000.source0000_split_lsrk.ps.zarr"
convert_msv2_to_processing_set(
    in_file=ms_file,
    out_file=outfile,
    parallel_mode="none",
    persistence_mode='w',
    main_chunksize=main_chunksize,
)

[2026-04-20 15:19:36,642]     INFO   toolviper:  Updated partition scheme used: ['DATA_DESC_ID', 'OBSERVATION_ID']
[2026-04-20 15:19:36,643]     INFO   toolviper:  Number of partitions: 2
[2026-04-20 15:19:36,643]     INFO   toolviper:  OBSERVATION_ID [0], DDI [0], STATE [None], FIELD [0], SCAN [0], EPHEMERIS [None]
[2026-04-20 15:19:36,717]  WARNING   toolviper:  Source_id is -1. No source information will be included in the field_and_source_xds.
[2026-04-20 15:19:37,145]     INFO   toolviper:  OBSERVATION_ID [0], DDI [1], STATE [None], FIELD [0], SCAN [0], EPHEMERIS [None]
[2026-04-20 15:19:37,217]  WARNING   toolviper:  Source_id is -1. No source information will be included in the field_and_source_xds.

Processing Set

from xradio.measurement_set import open_processing_set

ps_xdt = open_processing_set(ps_store=outfile)
ps_xdt.xr_ps.summary()

	name	scan_intents	shape	execution_block_UID	polarization	scan_name	spw_name	spw_intents	field_name	source_name	line_name	field_coords	session_reference_UID	scheduling_block_UID	project_UID	start_frequency	end_frequency
0	ngEHT_E17A10.0.bin0000.source0000_split_0	[None]	(2250, 20, 7, 4)	---	[RR, RL, LR, LL]	[0]	spw_0	[UNSPECIFIED]	[3C279_0]	[Unknown]	[]	[fk5, 12h56m11.17s, -5d47m21.52s]	---	---	E17A10	2.286593e+11	2.286623e+11
1	ngEHT_E17A10.0.bin0000.source0000_split_1	[None]	(2250, 20, 8, 4)	---	[RR, RL, LR, LL]	[0]	spw_1	[UNSPECIFIED]	[3C279_0]	[Unknown]	[]	[fk5, 12h56m11.17s, -5d47m21.52s]	---	---	E17A10	2.298723e+11	2.298758e+11

ms_xdt = ps_xdt["ngEHT_E17A10.0.bin0000.source0000_split_0"]
ms_xdt

<xarray.DataTree 'ngEHT_E17A10.0.bin0000.source0000_split_0'>
Group: /ngEHT_E17A10.0.bin0000.source0000_split_0
│   Dimensions:                     (time: 2250, baseline_id: 20, frequency: 7,
│                                    polarization: 4, uvw_label: 3)
│   Coordinates:
│     * time                        (time) float64 18kB 1.492e+09 ... 1.492e+09
│       field_name                  (time) <U27 243kB dask.array<chunksize=(2250,), meta=np.ndarray>
│       scan_name                   (time) <U21 189kB dask.array<chunksize=(2250,), meta=np.ndarray>
│     * baseline_id                 (baseline_id) int64 160B 0 1 2 3 ... 16 17 18 19
│       baseline_antenna1_name      (baseline_id) <U2 160B dask.array<chunksize=(20,), meta=np.ndarray>
│       baseline_antenna2_name      (baseline_id) <U2 160B dask.array<chunksize=(20,), meta=np.ndarray>
│     * frequency                   (frequency) float64 56B 2.287e+11 ... 2.287e+11
│     * polarization                (polarization) <U2 32B 'RR' 'RL' 'LR' 'LL'
│     * uvw_label                   (uvw_label) <U1 12B 'u' 'v' 'w'
│   Data variables:
│       EFFECTIVE_INTEGRATION_TIME  (time, baseline_id) float64 360kB dask.array<chunksize=(20, 20), meta=np.ndarray>
│       FLAG                        (time, baseline_id, frequency, polarization) bool 1MB dask.array<chunksize=(20, 20, 1, 4), meta=np.ndarray>
│       TIME_CENTROID               (time, baseline_id) float64 360kB dask.array<chunksize=(20, 20), meta=np.ndarray>
│       UVW                         (time, baseline_id, uvw_label) float64 1MB dask.array<chunksize=(20, 20, 3), meta=np.ndarray>
│       VISIBILITY                  (time, baseline_id, frequency, polarization) complex64 10MB dask.array<chunksize=(20, 20, 1, 4), meta=np.ndarray>
│       WEIGHT                      (time, baseline_id, frequency, polarization) float32 5MB dask.array<chunksize=(20, 20, 1, 4), meta=np.ndarray>
│   Attributes:
│       creation_date:     2026-04-20T21:19:36.659187+00:00
│       creator:           {'software_name': 'xradio', 'version': '1.1.3'}
│       data_groups:       {'base': {'correlated_data': 'VISIBILITY', 'date': '20...
│       observation_info:  {'observer': ['PLUTO'], 'observing_log': '[]', 'projec...
│       processor_info:    {'sub_type': '', 'type': ''}
│       schema_version:    4.0.0
│       type:              visibility
├── Group: /ngEHT_E17A10.0.bin0000.source0000_split_0/antenna_xds
│       Dimensions:                 (antenna_name: 6, cartesian_pos_label: 3,
│                                    receptor_label: 2)
│       Coordinates:
│         * antenna_name            (antenna_name) <U2 48B 'AA' 'AP' 'AZ' 'LM' 'PV' 'SP'
│           mount                   (antenna_name) <U16 384B dask.array<chunksize=(6,), meta=np.ndarray>
│           station_name            (antenna_name) <U2 48B dask.array<chunksize=(6,), meta=np.ndarray>
│           telescope_name          (antenna_name) <U4 96B dask.array<chunksize=(6,), meta=np.ndarray>
│         * cartesian_pos_label     (cartesian_pos_label) <U1 12B 'x' 'y' 'z'
│         * receptor_label          (receptor_label) <U5 40B 'pol_0' 'pol_1'
│           polarization_type       (antenna_name, receptor_label) <U1 48B dask.array<chunksize=(6, 2), meta=np.ndarray>
│       Data variables:
│           ANTENNA_DISH_DIAMETER   (antenna_name) float64 48B dask.array<chunksize=(6,), meta=np.ndarray>
│           ANTENNA_POSITION        (antenna_name, cartesian_pos_label) float64 144B dask.array<chunksize=(6, 3), meta=np.ndarray>
│           ANTENNA_RECEPTOR_ANGLE  (antenna_name, receptor_label) float64 96B dask.array<chunksize=(6, 2), meta=np.ndarray>
│       Attributes:
│           overall_telescope_name:  VLBA
│           relocatable_antennas:    False
│           type:                    antenna
└── Group: /ngEHT_E17A10.0.bin0000.source0000_split_0/field_and_source_base_xds
        Dimensions:                       (field_name: 1, sky_dir_label: 2)
        Coordinates:
          * field_name                    (field_name) <U27 108B '3C279_0'
            source_name                   (field_name) <U7 28B dask.array<chunksize=(1,), meta=np.ndarray>
          * sky_dir_label                 (sky_dir_label) <U3 24B 'ra' 'dec'
        Data variables:
            FIELD_PHASE_CENTER_DIRECTION  (field_name, sky_dir_label) float64 16B dask.array<chunksize=(1, 2), meta=np.ndarray>
        Attributes:
            type:     field_and_source

xarray.DataTree

'ngEHT_E17A10.0.bin0000.source0000_split_0'

• /ngEHT_E17A10.0.bin0000.source0000_split_0/antenna_xds(13)

  • Dimensions:
    • time: 2250
    • baseline_id: 20
    • frequency: 7
    • polarization: 4
    • uvw_label: 3
    • antenna_name: 6
    • cartesian_pos_label: 3
    • receptor_label: 2
  • Coordinates: (7)
    • antenna_name
      (antenna_name)
      <U2
      'AA' 'AP' 'AZ' 'LM' 'PV' 'SP'

      array(['AA', 'AP', 'AZ', 'LM', 'PV', 'SP'], dtype='<U2')

    • mount
      (antenna_name)
      <U16
      dask.array<chunksize=(6,), meta=np.ndarray>

      Array Chunk Bytes 384 B 384 B Shape (6,) (6,) Dask graph 1 chunks in 2 graph layers Data type

    • station_name
      (antenna_name)
      <U2
      dask.array<chunksize=(6,), meta=np.ndarray>

      Array Chunk Bytes 48 B 48 B Shape (6,) (6,) Dask graph 1 chunks in 2 graph layers Data type

    • telescope_name
      (antenna_name)
      <U4
      dask.array<chunksize=(6,), meta=np.ndarray>

      Array Chunk Bytes 96 B 96 B Shape (6,) (6,) Dask graph 1 chunks in 2 graph layers Data type

    • cartesian_pos_label
      (cartesian_pos_label)
      <U1
      'x' 'y' 'z'

      array(['x', 'y', 'z'], dtype='<U1')

    • receptor_label
      (receptor_label)
      <U5
      'pol_0' 'pol_1'

      array(['pol_0', 'pol_1'], dtype='<U5')

    • polarization_type
      (antenna_name, receptor_label)
      <U1
      dask.array<chunksize=(6, 2), meta=np.ndarray>

      Array Chunk Bytes 48 B 48 B Shape (6, 2) (6, 2) Dask graph 1 chunks in 2 graph layers Data type

  • Data variables: (3)
    • ANTENNA_DISH_DIAMETER
      (antenna_name)
      float64
      dask.array<chunksize=(6,), meta=np.ndarray>

      type :

      quantity

      units :

      m

      Array Chunk Bytes 48 B 48 B Shape (6,) (6,) Dask graph 1 chunks in 2 graph layers Data type float64 numpy.ndarray

    • ANTENNA_POSITION
      (antenna_name, cartesian_pos_label)
      float64
      dask.array<chunksize=(6, 3), meta=np.ndarray>

      coordinate_system :

      geocentric

      frame :

      ITRS

      origin_object_name :

      earth

      type :

      location

      units :

      m

      Array Chunk Bytes 144 B 144 B Shape (6, 3) (6, 3) Dask graph 1 chunks in 2 graph layers Data type float64 numpy.ndarray

    • ANTENNA_RECEPTOR_ANGLE
      (antenna_name, receptor_label)
      float64
      dask.array<chunksize=(6, 2), meta=np.ndarray>

      type :

      quantity

      units :

      rad

      Array Chunk Bytes 96 B 96 B Shape (6, 2) (6, 2) Dask graph 1 chunks in 2 graph layers Data type float64 numpy.ndarray

  • Attributes: (3)

    overall_telescope_name :

    VLBA

    relocatable_antennas :

    False

    type :

    antenna

  /ngEHT_E17A10.0.bin0000.source0000_split_0/field_and_source_base_xds(5)

  • Dimensions:
    • time: 2250
    • baseline_id: 20
    • frequency: 7
    • polarization: 4
    • uvw_label: 3
    • field_name: 1
    • sky_dir_label: 2
  • Coordinates: (3)
    • field_name
      (field_name)
      <U27
      '3C279_0'

      array(['3C279_0'], dtype='<U27')

    • source_name
      (field_name)
      <U7
      dask.array<chunksize=(1,), meta=np.ndarray>

      Array Chunk Bytes 28 B 28 B Shape (1,) (1,) Dask graph 1 chunks in 2 graph layers Data type

    • sky_dir_label
      (sky_dir_label)
      <U3
      'ra' 'dec'

      array(['ra', 'dec'], dtype='<U3')

  • Data variables: (1)
    • FIELD_PHASE_CENTER_DIRECTION
      (field_name, sky_dir_label)
      float64
      dask.array<chunksize=(1, 2), meta=np.ndarray>

      frame :

      fk5

      type :

      sky_coord

      units :

      rad

      Array Chunk Bytes 16 B 16 B Shape (1, 2) (1, 2) Dask graph 1 chunks in 2 graph layers Data type float64 numpy.ndarray

  • Attributes: (1)

    type :

    field_and_source

• Dimensions:
  • time: 2250
  • baseline_id: 20
  • frequency: 7
  • polarization: 4
  • uvw_label: 3
• Coordinates: (9)
  • time
    (time)
    float64
    1.492e+09 1.492e+09 ... 1.492e+09

    format :

    unix

    integration_time :

    {'attrs': {'type': 'quantity', 'units': 's'}, 'data': 0.4000000059604645, 'dims': []}

    scale :

    utc

    type :

    time

    units :

    s

    array([1.491790e+09, 1.491790e+09, 1.491790e+09, ..., 1.491795e+09,
           1.491795e+09, 1.491795e+09], shape=(2250,))

  • field_name
    (time)
    <U27
    dask.array<chunksize=(2250,), meta=np.ndarray>

    Array Chunk Bytes 237.30 kiB 237.30 kiB Shape (2250,) (2250,) Dask graph 1 chunks in 2 graph layers Data type

  • scan_name
    (time)
    <U21
    dask.array<chunksize=(2250,), meta=np.ndarray>

    scan_intents :

    ['None']

    Array Chunk Bytes 184.57 kiB 184.57 kiB Shape (2250,) (2250,) Dask graph 1 chunks in 2 graph layers Data type

  • baseline_id
    (baseline_id)
    int64
    0 1 2 3 4 5 6 ... 14 15 16 17 18 19

    array([ 0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11, 12, 13, 14, 15, 16, 17,
           18, 19])

  • baseline_antenna1_name
    (baseline_id)
    <U2
    dask.array<chunksize=(20,), meta=np.ndarray>

    Array Chunk Bytes 160 B 160 B Shape (20,) (20,) Dask graph 1 chunks in 2 graph layers Data type

  • baseline_antenna2_name
    (baseline_id)
    <U2
    dask.array<chunksize=(20,), meta=np.ndarray>

    Array Chunk Bytes 160 B 160 B Shape (20,) (20,) Dask graph 1 chunks in 2 graph layers Data type

  • frequency
    (frequency)
    float64
    2.287e+11 2.287e+11 ... 2.287e+11

    channel_width :

    {'attrs': {'type': 'quantity', 'units': 'Hz'}, 'data': 500000.0, 'dims': []}

    observer :

    gcrs

    reference_frequency :

    {'attrs': {'observer': 'gcrs', 'type': 'spectral_coord', 'units': 'Hz'}, 'data': 228659289062.5, 'dims': []}

    spectral_window_intents :

    ['UNSPECIFIED']

    spectral_window_name :

    spw_0

    type :

    spectral_coord

    units :

    Hz

    array([2.286593e+11, 2.286598e+11, 2.286603e+11, 2.286608e+11, 2.286613e+11,
           2.286618e+11, 2.286623e+11])

  • polarization
    (polarization)
    <U2
    'RR' 'RL' 'LR' 'LL'

    array(['RR', 'RL', 'LR', 'LL'], dtype='<U2')

  • uvw_label
    (uvw_label)
    <U1
    'u' 'v' 'w'

    array(['u', 'v', 'w'], dtype='<U1')

• Data variables: (6)
  • EFFECTIVE_INTEGRATION_TIME
    (time, baseline_id)
    float64
    dask.array<chunksize=(20, 20), meta=np.ndarray>

    type :

    quantity

    units :

    s

    Array Chunk Bytes 351.56 kiB 3.12 kiB Shape (2250, 20) (20, 20) Dask graph 113 chunks in 2 graph layers Data type float64 numpy.ndarray

  • FLAG
    (time, baseline_id, frequency, polarization)
    bool
    dask.array<chunksize=(20, 20, 1, 4), meta=np.ndarray>

    Array Chunk Bytes 1.20 MiB 1.56 kiB Shape (2250, 20, 7, 4) (20, 20, 1, 4) Dask graph 791 chunks in 2 graph layers Data type bool numpy.ndarray

  • TIME_CENTROID
    (time, baseline_id)
    float64
    dask.array<chunksize=(20, 20), meta=np.ndarray>

    format :

    unix

    scale :

    utc

    type :

    time

    units :

    s

    Array Chunk Bytes 351.56 kiB 3.12 kiB Shape (2250, 20) (20, 20) Dask graph 113 chunks in 2 graph layers Data type float64 numpy.ndarray

  • UVW
    (time, baseline_id, uvw_label)
    float64
    dask.array<chunksize=(20, 20, 3), meta=np.ndarray>

    frame :

    fk5

    type :

    uvw

    units :

    m

    Array Chunk Bytes 1.03 MiB 9.38 kiB Shape (2250, 20, 3) (20, 20, 3) Dask graph 113 chunks in 2 graph layers Data type float64 numpy.ndarray

  • VISIBILITY
    (time, baseline_id, frequency, polarization)
    complex64
    dask.array<chunksize=(20, 20, 1, 4), meta=np.ndarray>

    type :

    quanta

    units :

    unkown

    Array Chunk Bytes 9.61 MiB 12.50 kiB Shape (2250, 20, 7, 4) (20, 20, 1, 4) Dask graph 791 chunks in 2 graph layers Data type complex64 numpy.ndarray

  • WEIGHT
    (time, baseline_id, frequency, polarization)
    float32
    dask.array<chunksize=(20, 20, 1, 4), meta=np.ndarray>

    type :

    quanta

    units :

    unkown

    Array Chunk Bytes 4.81 MiB 6.25 kiB Shape (2250, 20, 7, 4) (20, 20, 1, 4) Dask graph 791 chunks in 2 graph layers Data type float32 numpy.ndarray

• Attributes: (7)

  creation_date :

  2026-04-20T21:19:36.659187+00:00

  creator :

  {'software_name': 'xradio', 'version': '1.1.3'}

  data_groups :

  {'base': {'correlated_data': 'VISIBILITY', 'date': '2026-04-20T21:19:36.697770+00:00', 'description': "Data group derived from the data column 'VISIBILITY' of an MSv2 converted to MSv4", 'field_and_source': 'field_and_source_base_xds', 'flag': 'FLAG', 'uvw': 'UVW', 'weight': 'WEIGHT'}}

  observation_info :

  {'observer': ['PLUTO'], 'observing_log': '[]', 'project_UID': 'E17A10', 'release_date': '2017-04-10T01:59:00.199999809'}

  processor_info :

  {'sub_type': '', 'type': ''}

  schema_version :

  4.0.0

  type :

  visibility

ms_xdt.antenna_xds.compute()

<xarray.DataTree 'antenna_xds'>
Group: /
    Dimensions:                 (time: 2250, baseline_id: 20, frequency: 7,
                                 polarization: 4, uvw_label: 3, antenna_name: 6,
                                 cartesian_pos_label: 3, receptor_label: 2)
    Coordinates:
      * time                    (time) float64 18kB 1.492e+09 ... 1.492e+09
      * baseline_id             (baseline_id) int64 160B 0 1 2 3 4 ... 16 17 18 19
      * frequency               (frequency) float64 56B 2.287e+11 ... 2.287e+11
      * polarization            (polarization) <U2 32B 'RR' 'RL' 'LR' 'LL'
      * uvw_label               (uvw_label) <U1 12B 'u' 'v' 'w'
      * antenna_name            (antenna_name) <U2 48B 'AA' 'AP' 'AZ' 'LM' 'PV' 'SP'
        mount                   (antenna_name) <U16 384B 'ALT-AZ' ... 'ALT-AZ'
        station_name            (antenna_name) <U2 48B 'AA' 'AP' 'AZ' 'LM' 'PV' 'SP'
        telescope_name          (antenna_name) <U4 96B 'VLBA' 'VLBA' ... 'VLBA'
      * cartesian_pos_label     (cartesian_pos_label) <U1 12B 'x' 'y' 'z'
      * receptor_label          (receptor_label) <U5 40B 'pol_0' 'pol_1'
        polarization_type       (antenna_name, receptor_label) <U1 48B 'R' ... 'L'
    Data variables:
        ANTENNA_DISH_DIAMETER   (antenna_name) float64 48B 12.0 12.0 ... 30.0 10.0
        ANTENNA_POSITION        (antenna_name, cartesian_pos_label) float64 144B ...
        ANTENNA_RECEPTOR_ANGLE  (antenna_name, receptor_label) float64 96B 0.0 .....
    Attributes:
        overall_telescope_name:  VLBA
        relocatable_antennas:    False
        type:                    antenna

xarray.DataTree

'antenna_xds'

• Dimensions:
  • time: 2250
  • baseline_id: 20
  • frequency: 7
  • polarization: 4
  • uvw_label: 3
  • antenna_name: 6
  • cartesian_pos_label: 3
  • receptor_label: 2
• Coordinates: (12)
  • time
    (time)
    float64
    1.492e+09 1.492e+09 ... 1.492e+09

    format :

    unix

    integration_time :

    {'attrs': {'type': 'quantity', 'units': 's'}, 'data': 0.4000000059604645, 'dims': []}

    scale :

    utc

    type :

    time

    units :

    s

    array([1.491790e+09, 1.491790e+09, 1.491790e+09, ..., 1.491795e+09,
           1.491795e+09, 1.491795e+09], shape=(2250,))

  • baseline_id
    (baseline_id)
    int64
    0 1 2 3 4 5 6 ... 14 15 16 17 18 19

    array([ 0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11, 12, 13, 14, 15, 16, 17,
           18, 19])

  • frequency
    (frequency)
    float64
    2.287e+11 2.287e+11 ... 2.287e+11

    channel_width :

    {'attrs': {'type': 'quantity', 'units': 'Hz'}, 'data': 500000.0, 'dims': []}

    observer :

    gcrs

    reference_frequency :

    {'attrs': {'observer': 'gcrs', 'type': 'spectral_coord', 'units': 'Hz'}, 'data': 228659289062.5, 'dims': []}

    spectral_window_intents :

    ['UNSPECIFIED']

    spectral_window_name :

    spw_0

    type :

    spectral_coord

    units :

    Hz

    array([2.286593e+11, 2.286598e+11, 2.286603e+11, 2.286608e+11, 2.286613e+11,
           2.286618e+11, 2.286623e+11])

  • polarization
    (polarization)
    <U2
    'RR' 'RL' 'LR' 'LL'

    array(['RR', 'RL', 'LR', 'LL'], dtype='<U2')

  • uvw_label
    (uvw_label)
    <U1
    'u' 'v' 'w'

    array(['u', 'v', 'w'], dtype='<U1')

  • antenna_name
    (antenna_name)
    <U2
    'AA' 'AP' 'AZ' 'LM' 'PV' 'SP'

    array(['AA', 'AP', 'AZ', 'LM', 'PV', 'SP'], dtype='<U2')

  • mount
    (antenna_name)
    <U16
    'ALT-AZ' ... 'ALT-AZ'

    array(['ALT-AZ', 'ALT-AZ+NASMYTH-L', 'ALT-AZ+NASMYTH-R',
           'ALT-AZ+NASMYTH-L', 'ALT-AZ+NASMYTH-L', 'ALT-AZ'], dtype='<U16')

  • station_name
    (antenna_name)
    <U2
    'AA' 'AP' 'AZ' 'LM' 'PV' 'SP'

    array(['AA', 'AP', 'AZ', 'LM', 'PV', 'SP'], dtype='<U2')

  • telescope_name
    (antenna_name)
    <U4
    'VLBA' 'VLBA' ... 'VLBA' 'VLBA'

    array(['VLBA', 'VLBA', 'VLBA', 'VLBA', 'VLBA', 'VLBA'], dtype='<U4')

  • cartesian_pos_label
    (cartesian_pos_label)
    <U1
    'x' 'y' 'z'

    array(['x', 'y', 'z'], dtype='<U1')

  • receptor_label
    (receptor_label)
    <U5
    'pol_0' 'pol_1'

    array(['pol_0', 'pol_1'], dtype='<U5')

  • polarization_type
    (antenna_name, receptor_label)
    <U1
    'R' 'L' 'R' 'L' ... 'R' 'L' 'R' 'L'

    array([['R', 'L'],
           ['R', 'L'],
           ['R', 'L'],
           ['R', 'L'],
           ['R', 'L'],
           ['R', 'L']], dtype='<U1')

• Data variables: (3)
  • ANTENNA_DISH_DIAMETER
    (antenna_name)
    float64
    12.0 12.0 10.0 50.0 30.0 10.0

    type :

    quantity

    units :

    m

    array([12., 12., 10., 50., 30., 10.])

  • ANTENNA_POSITION
    (antenna_name, cartesian_pos_label)
    float64
    2.225e+06 -5.44e+06 ... -6.36e+06

    coordinate_system :

    geocentric

    frame :

    ITRS

    origin_object_name :

    earth

    type :

    location

    units :

    m

    array([[ 2.22506128e+06, -5.44006174e+06, -2.48168115e+06],
           [ 2.22503953e+06, -5.44119763e+06, -2.47930336e+06],
           [-1.82879620e+06, -5.05440680e+06,  3.42786520e+06],
           [-7.68715632e+05, -5.98850707e+06,  2.06335485e+06],
           [ 5.08896775e+06, -3.01681186e+05,  3.82501221e+06],
           [ 8.09761600e+02, -8.16848000e+02, -6.35956873e+06]])

  • ANTENNA_RECEPTOR_ANGLE
    (antenna_name, receptor_label)
    float64
    0.0 0.0 0.0 0.0 ... 0.0 0.0 0.0 0.0

    type :

    quantity

    units :

    rad

    array([[0., 0.],
           [0., 0.],
           [0., 0.],
           [0., 0.],
           [0., 0.],
           [0., 0.]])

• Attributes: (3)

  overall_telescope_name :

  VLBA

  relocatable_antennas :

  False

  type :

  antenna

ms_xdt.xr_ms.get_field_and_source_xds()

<xarray.DatasetView> Size: 18kB
Dimensions:                       (field_name: 1, sky_dir_label: 2,
                                   baseline_id: 20, frequency: 7,
                                   polarization: 4, time: 2250, uvw_label: 3)
Coordinates:
  * field_name                    (field_name) <U27 108B '3C279_0'
    source_name                   (field_name) <U7 28B dask.array<chunksize=(1,), meta=np.ndarray>
  * sky_dir_label                 (sky_dir_label) <U3 24B 'ra' 'dec'
  * baseline_id                   (baseline_id) int64 160B 0 1 2 3 ... 17 18 19
  * frequency                     (frequency) float64 56B 2.287e+11 ... 2.287...
  * polarization                  (polarization) <U2 32B 'RR' 'RL' 'LR' 'LL'
  * time                          (time) float64 18kB 1.492e+09 ... 1.492e+09
  * uvw_label                     (uvw_label) <U1 12B 'u' 'v' 'w'
Data variables:
    FIELD_PHASE_CENTER_DIRECTION  (field_name, sky_dir_label) float64 16B dask.array<chunksize=(1, 2), meta=np.ndarray>
Attributes:
    type:     field_and_source

xarray.DatasetView

• Dimensions:
  • field_name: 1
  • sky_dir_label: 2
  • baseline_id: 20
  • frequency: 7
  • polarization: 4
  • time: 2250
  • uvw_label: 3
• Coordinates: (8)
  • field_name
    (field_name)
    <U27
    '3C279_0'

    array(['3C279_0'], dtype='<U27')

  • source_name
    (field_name)
    <U7
    dask.array<chunksize=(1,), meta=np.ndarray>

    Array Chunk Bytes 28 B 28 B Shape (1,) (1,) Dask graph 1 chunks in 2 graph layers Data type

  • sky_dir_label
    (sky_dir_label)
    <U3
    'ra' 'dec'

    array(['ra', 'dec'], dtype='<U3')

  • baseline_id
    (baseline_id)
    int64
    0 1 2 3 4 5 6 ... 14 15 16 17 18 19

    array([ 0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11, 12, 13, 14, 15, 16, 17,
           18, 19])

  • frequency
    (frequency)
    float64
    2.287e+11 2.287e+11 ... 2.287e+11

    channel_width :

    {'attrs': {'type': 'quantity', 'units': 'Hz'}, 'data': 500000.0, 'dims': []}

    observer :

    gcrs

    reference_frequency :

    {'attrs': {'observer': 'gcrs', 'type': 'spectral_coord', 'units': 'Hz'}, 'data': 228659289062.5, 'dims': []}

    spectral_window_intents :

    ['UNSPECIFIED']

    spectral_window_name :

    spw_0

    type :

    spectral_coord

    units :

    Hz

    array([2.286593e+11, 2.286598e+11, 2.286603e+11, 2.286608e+11, 2.286613e+11,
           2.286618e+11, 2.286623e+11])

  • polarization
    (polarization)
    <U2
    'RR' 'RL' 'LR' 'LL'

    array(['RR', 'RL', 'LR', 'LL'], dtype='<U2')

  • time
    (time)
    float64
    1.492e+09 1.492e+09 ... 1.492e+09

    format :

    unix

    integration_time :

    {'attrs': {'type': 'quantity', 'units': 's'}, 'data': 0.4000000059604645, 'dims': []}

    scale :

    utc

    type :

    time

    units :

    s

    array([1.491790e+09, 1.491790e+09, 1.491790e+09, ..., 1.491795e+09,
           1.491795e+09, 1.491795e+09], shape=(2250,))

  • uvw_label
    (uvw_label)
    <U1
    'u' 'v' 'w'

    array(['u', 'v', 'w'], dtype='<U1')

• Data variables: (1)
  • FIELD_PHASE_CENTER_DIRECTION
    (field_name, sky_dir_label)
    float64
    dask.array<chunksize=(1, 2), meta=np.ndarray>

    frame :

    fk5

    type :

    sky_coord

    units :

    rad

    Array Chunk Bytes 16 B 16 B Shape (1, 2) (1, 2) Dask graph 1 chunks in 2 graph layers Data type float64 numpy.ndarray

• Attributes: (1)

  type :

  field_and_source

ps_xdt.xr_ps.plot_antenna_positions_2d()

ps_xdt.xr_ps.plot_phase_centers()