Obslist

Return to Analysis Utilities

This page documents the obslist function of Python module analysisUtils.

In CASA, task listobs tells you the antenna positions in Longitude and Latitude. Sometimes it's informative to know the positions in a local offset coordinate system, and what the min/max baseline lengths are. This function parses the telescope name from the OBSERVATION table, then finds the coordinates of the center of the array (COFA), then converts each station coordinates into local offsets in meters from the COFA and prints the information. See also plotconfig.

Examples

# In CASA
au.obslist('Band7multi_april22.ms')

Antenna  0 = DV04 on pad J505, lat/long offset (m) =    -7.2138/ -488.2036
Antenna  1 = DV06 on pad T704, lat/long offset (m) =   +42.8973/ -465.4952
Antenna  2 = DV07 on pad J510, lat/long offset (m) =    -0.3652/ -512.3043
Antenna  3 = DV08 on pad T703, lat/long offset (m) =   +42.8783/ -525.0569
Antenna  4 = DV09 on pad N602, lat/long offset (m) =    +8.8009/ -473.7260
Antenna  5 = DV10 on pad N606, lat/long offset (m) =   +19.1975/ -515.2704
Antenna  6 = PM01 on pad T702, lat/long offset (m) =   -23.6261/ -532.1683
Antenna  7 = PM02 on pad T701, lat/long offset (m) =   -29.1258/ -468.2863
Antenna  8 = PM03 on pad J504, lat/long offset (m) =   +22.2007/ -497.7628
Longest baseline = 91.018 m = DV06-PM01
Shortest baseline = 16.586 m = DV10-PM03

In some cases it may be useful to use one Antenna's position as a reference rather than the center of the array stored in casa. To do this, simply specify the antenna ID or its name:

# In CASA
au.obslist('Band7multi_april22.ms',cofa=8)

Antenna  0 = DV04 on pad J505, lat/long offset (m) =   -29.4146/   +9.5595
Antenna  1 = DV06 on pad T704, lat/long offset (m) =   +20.6965/  +32.2686
Antenna  2 = DV07 on pad J510, lat/long offset (m) =   -22.5659/  -14.5420
Antenna  3 = DV08 on pad T703, lat/long offset (m) =   +20.6775/  -27.2949
Antenna  4 = DV09 on pad N602, lat/long offset (m) =   -13.3998/  +24.0375
Antenna  5 = DV10 on pad N606, lat/long offset (m) =    -3.0033/  -17.5081
Antenna  6 = PM01 on pad T702, lat/long offset (m) =   -45.8268/  -34.4065
Antenna  7 = PM02 on pad T701, lat/long offset (m) =   -51.3266/  +29.4773
Antenna  8 = PM03 on pad J504, lat/long offset (m) =    +0.0000/   +0.0000
Longest baseline = 91.018 m = DV06-PM01
Shortest baseline = 16.586 m = DV10-PM03

# In CASA
au.obslist('Band7multi_april22.ms',cofa='DV06')

Antenna DV06 has ID 1
Antenna  0 = DV04 on pad J505, lat/long offset (m) =   -50.1111/  -22.7091
Antenna  1 = DV06 on pad T704, lat/long offset (m) =    +0.0000/   +0.0000
Antenna  2 = DV07 on pad J510, lat/long offset (m) =   -43.2624/  -46.8105
Antenna  3 = DV08 on pad T703, lat/long offset (m) =    -0.0189/  -59.5634
Antenna  4 = DV09 on pad N602, lat/long offset (m) =   -34.0964/   -8.2312
Antenna  5 = DV10 on pad N606, lat/long offset (m) =   -23.6997/  -49.7767
Antenna  6 = PM01 on pad T702, lat/long offset (m) =   -66.5232/  -66.6751
Antenna  7 = PM02 on pad T701, lat/long offset (m) =   -72.0231/   -2.7914
Antenna  8 = PM03 on pad J504, lat/long offset (m) =   -20.6965/  -32.2686
Longest baseline = 91.018 m = DV06-PM01
Shortest baseline = 16.586 m = DV10-PM03