mwax_stats

The mwax correlator exectutes mwax_stats for each visibility FITS file created. mwax_stats uses mwalib to read the visibilities then output various stats dumps which are used by the M&C system to provide near-realtime plots allowing a human to verify correlator output is ok.

Usage

USAGE:
    mwax_stats <fits-files>... -m <metafits> -o <output-dir>

FLAGS:
    -h, --help       Prints help information
    -V, --version    Prints version information

OPTIONS:
    -m <metafits>          Sets the metafits file.
    -o <output-dir>        Specify the directory to write output files to.

ARGS:
    <fits-files>...

Since mwax_stats utilises the env_logger and log crates, you can set different levels of logging output using the RUST_LOG variable: RUST_LOG=info|debug|trace mwax_stats.... The info logging level is the least verbose, and trace is the most- it will output a line of debug for each unit of data written (you have been warned!).

Auto-correlation output

mwax_stats will output power (in dB) for XX and YY vs frequency for all tiles for all provided coarse channels for the last timestep in the observation.

Auto-correlation: Filename

• filename = OOOOOOOOOO_autos_FFFFchans_NNNT_chRRR.dat e.g. 1317706936_autos_64chans_128T_ch123.dat would describe obsid 1317706936, 64 fine channels per coarse and 128 tiles for receiver coarse channel 123.
  • Where:
    • OOOOOOOOOO = Obsid
    • FFFF = number of fine channels. Could be 1,2,3 or 4 digits depending on the correlator mode
    • NNN = number of tiles
    • RRR = receiver coarse channel number. Could be 1,2 or 3 digits

Auto-correlation: Output format

• for each tile:
  • for each fine channel:
    • 3 float32 values:
      • Frequency (MHz)
      • XX power (dB)
      • YY power (dB)
• Tiles are in "antenna" order

Fringes output

mwax_stats will also output phase (XX and YY) vs frequency for all baselines for all provided coarse channels for the last timestep in the observation.

Fringes: Filename

• filename = OOOOOOOOOO_fringes_FFFFchans_NNNT_chRRR.dat e.g. 1317706936_fringes_64chans_128T_ch123.dat would describe obsid 1317706936, 64 fine channels per coarse and 128 tiles for receiver coarse channel 123.
  • Where:
    • OOOOOOOOOO = Obsid
    • FFFF = number of fine channels. Could be 1,2,3 or 4 digits depending on the correlator mode
    • NNN = number of tiles
    • RRR = receiver coarse channel number. Could be 1,2 or 3 digits

Fringes: Output format

• for each baseline:
  • for each fine channel:
    • 3 float32 values:
      • Frequency (MHz)
      • XX phase (degrees)
      • YY phase (degrees)
• Baselines are in lower right triangular order with tile1 vs tile2. Example below for 128 tiles:
  • 0 v 0
  • 0 v 1
  • ...
  • 0 v 127
  • 1 v 1
  • 1 v 2
  • ...
  • 1 v 127
  • ...
  • 127 v 127
• Tiles are in "antenna" order