importuvfits

importuvfits(fitsfile, vis='', antnamescheme='old')[source]

Convert a UVFITS file to a CASA visibility data set

[Description] [Examples] [Development] [Details]

Parameters

  • fitsfile (path) - Name of input UV FITS file

  • vis (string=’’) - Name of output visibility file (MS)

  • antnamescheme (string=’old’) - VLA/EVLA/CARMA only; 'new' or 'old'; 'VA04' or '04' for VLA ant 4

Description

This is primarily designed for importing AIPS data into CASA, but also works for other UVFITS data (e.g., MIRIAD).

The current UVFITS specification can be found in AIPS Memo 117.

The antnamescheme parameter specifies the naming scheme for VLA/JVLA/CARMA antennas. The default is “old”. For “old”, antnnea names are numerical, eg “04”. This option exists for backwards compatibility but can lead to ambiguous results when antenna indices are used for data selection. When set to “new”, Antenna names are not strictly numerical, eg “VA04” or “EA04”. With this scheme, data selection via antenna names and indices is non-ambiguous.

A NOTE ON WEIGHTS: importuvfits will generate a WEIGHT_SPECTRUM column in which it will fill the absolute value of the weight associated with each visibility in the uvfits file. Negative weights will have the associated FLAGs set to True. It will compute the associated WEIGHT value for that MS row to be the sum of the absolute values of the associated WEIGHT_SPECTRUM values.

Warning

Importing of MSs with Nant>255 via importuvfits should be considered experimental and datasets transported this way may not behave as expected in other packages (e.g., AIPS).

Note

Remember to flag the autocorrelations if you do not want them, using the task flagdata with parameter autocorr = true

Examples
importuvfits(fitsfile="my.uvfits", vis="my.ms")
Development

No additional development details

Parameter Details

Detailed descriptions of each function parameter

fitsfile (path) - Name of input UV FITS file
vis (string='') - Name of output visibility file (MS)
antnamescheme (string='old') - VLA/EVLA/CARMA only; 'new' or 'old'; 'VA04' or '04' for VLA ant 4