UVCal Class

UVCal is the main user class for calibration solutions. It provides import and export functionality to all supported file formats (calfits) and can be interacted with directly.

class pyuvdata.UVCal[source]

A class defining calibration solutions

Currently supported file types: calfits

UVParameter objects

For full list see UVCal Parameters (http://pyuvdata.readthedocs.io/en/latest/uvcal.html). Some are always required, some are required for certain cal_types and others are always optional.

check(check_extra=True, run_check_acceptability=True)[source]

Check that all required parameters are set reasonably.

Check that required parameters exist and have appropriate shapes. Optionally check if the values are acceptable.

Parameters

run_check_acceptability – Option to check if values in required parameters are acceptable. Default is True.

set_gain()[source]

Set cal_type to ‘gain’ and adjust required parameters.

set_delay()[source]

Set cal_type to ‘delay’ and adjust required parameters.

set_unknown_cal_type()[source]

Set cal_type to ‘unknown’ and adjust required parameters.

set_sky()[source]

Set cal_style to ‘sky’ and adjust required parameters.

set_redundant()[source]

Set cal_style to ‘redundant’ and adjust required parameters.

select(antenna_nums=None, antenna_names=None, frequencies=None, freq_chans=None, times=None, jones=None, run_check=True, check_extra=True, run_check_acceptability=True, inplace=True)[source]

Select specific antennas, frequencies, times and jones polarization terms to keep in the object while discarding others.

The history attribute on the object will be updated to identify the operations performed.

Parameters

  • antenna_nums – The antennas numbers to keep in the object (antenna positions and names for the removed antennas will be retained). This cannot be provided if antenna_names is also provided.

  • antenna_names – The antennas names to keep in the object (antenna positions and names for the removed antennas will be retained). This cannot be provided if antenna_nums is also provided.

  • frequencies – The frequencies to keep in the object.

  • freq_chans – The frequency channel numbers to keep in the object.

  • times – The times to keep in the object.

  • jones – The jones polarization terms to keep in the object.

  • run_check – Option to check for the existence and proper shapes of required parameters after downselecting data on this object. Default is True.

  • check_extra – Option to check shapes and types of optional parameters as well as required ones. Default is True.

  • run_check_acceptability – Option to check acceptable range of the values of required parameters after downselecting data on this object. Default is True.

  • inplace – Option to perform the select directly on self (True, default) or return a new UVCal object, which is a subselection of self (False)

convert_to_gain(delay_convention='minus', run_check=True, check_extra=True, run_check_acceptability=True)[source]

Convert non-gain cal_types to gains.

For the delay cal_type the gain is calculated as:

gain = 1 * exp((+/-) * 2 * pi * j * delay * frequency) where the (+/-) is dictated by the delay_convention

Parameters

  • delay_convention – exponent sign to use in the conversion. Defaults to minus.

  • run_check – Option to check for the existence and proper shapes of parameters after converting this object. Default is True.

  • check_extra – Option to check shapes and types of optional parameters as well as required ones. Default is True.

  • run_check_acceptability – Option to check acceptable range of the values of parameters after converting this object. Default is True.

read_calfits(filename, run_check=True, check_extra=True, run_check_acceptability=True, strict_fits=False)[source]

Read in data from a calfits file.

Parameters

  • filename – The calfits file or list of files to read from. string path, or list or tuple of string paths.

  • run_check – Option to check for the existence and proper shapes of parameters after reading in the file. Default is True.

  • check_extra – Option to check optional parameters as well as required ones. Default is True.

  • run_check_acceptability – Option to check acceptable range of the values of parameters after reading in the file. Default is True.

  • strict_fits – boolean If True, require that the data axes have cooresponding NAXIS, CRVAL, CDELT and CRPIX keywords. If False, allow CRPIX to be missing and set it equal to zero and allow the CRVAL for the spw directions to be missing and set it to zero. This keyword exists to support old calfits files that were missing many CRPIX and CRVAL keywords. Default is False.

write_calfits(filename, run_check=True, check_extra=True, run_check_acceptability=True, clobber=False)[source]

Write data to a calfits file.

Parameters

  • filename – The calfits filename to write to.

  • run_check – Option to check for the existence and proper shapes of parameters before writing the file. Default is True.

  • check_extra – Option to check optional parameters as well as required ones. Default is True.

  • run_check_acceptability – Option to check acceptable range of the values of parameters before writing the file. Default is True.

  • clobber – Option to overwrite the filename if the file already exists. Default is False.

read_fhd_cal(cal_file, obs_file, settings_file=None, raw=True, extra_history=None, run_check=True, check_extra=True, run_check_acceptability=True)[source]

Read data from an FHD cal.sav file.

Parameters

  • cal_file – The cal.sav file to read from.

  • obs_file – The obs.sav file to read from.

  • settings_file – The settings_file to read from. Optional, but very useful for provenance.

  • raw – Option to use the raw (per antenna, per frequency) solution or to use the fitted (polynomial over phase/amplitude) solution. Default is True (meaning use the raw solutions).

  • extra_history – Optional string or list of strings to add to the object’s history parameter. Default is None.

  • run_check – Option to check for the existence and proper shapes of parameters after reading in the file. Default is True.

  • check_extra – Option to check optional parameters as well as required ones. Default is True.

  • run_check_acceptability – Option to check acceptable range of the values of parameters after reading in the file. Default is True.