sdtimeaverage

sdtimeaverage(infile, datacolumn='float_data', field='', spw='', timerange='', scan='', antenna='', timebin='all', timespan='scan', outfile='')[source]

Average SD data, perform time averaging

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

Parameters
  • infile (path) - name of input SD dataset

  • datacolumn (string=’float_data’) - name of data column to be used [“data”, “float_data”, or “corrected_data”]

  • field (string=’’) - select data by field IDs and names, e.g. “3C2*” (“”=all)

  • spw (string=’’) - select data by spectral windows and channels, e.g. “3,5,7” (“”=all)

  • timerange (string=’’) - select data by time range, e.g. “09:14:0~09:54:0” (“”=all) (see examples in help)

  • scan (string=’’) - select data by scan numbers, e.g. “21~23” (“”=all)

  • antenna (string=’’) - antenna IDs to be averaged over, e.g. “PM03” (“”=all)

  • timebin (string=’all’) - bin width for time averaging.

  • timespan (string=’scan’) - span across scan, state or both.

  • outfile (string=’’) - name of output file

Description

Task sdtimeaverage is used for averaging SD spectral data over specified time or all the data and export output MS. Data selection is available. Please see parameters.

Task sdtimeaverage is a wrapper task of mstransform. sdtimeaveraging provides spectral data averaging in a simple way.

When All the spectra data is to be averaged, timebin=’all’ option is available. This option automatically obtains the actual time range, then internally executes mstransform.

If the parameter is not specified, sdtimeaverage uses the default values. If specified output MS already exist, sdtimeaverage does not overwrite.

Parameter Descriptions .. rubric:: timebin (default : ‘ ‘ (all))

The timebin parameter will perform time averaging in the specified bin width.

Warning

Warning: the timebin parameter works based on wall clock time, not integration time. For example, if each scan is 5 seconds long, and scans are separated by 15 seconds, then timebin=’25s’ is the minimum value needed to combine data from 2 consecutive scans. One might assume that timebin=’10s’ should work to combine two 5 second scans, but it does not.

timespan (default : ‘scan’)

The timespan parameter will span the timebin across scans, states or both. State is equivalent to sub-scans and one scan may have several state IDs.

  • ‘scan’: average data regardless of scan

  • ‘state’: average data regardless of state

  • ‘scan, state’: average data regardless of both scan and state

  • ‘ ‘: average data over each scan and each state separately

Warning

The timespan subparameter = ‘scan,scate’ performs average of the data regardless of scan and state. In some cases, data of ON-scan and OFF-scan are to be averaged. If the TELESCOPE NAME in specified MS contains ‘ALMA’, then mstransform automatically changes timescan = ‘scan state’.

timerange (default : ‘ ‘ (all))

The timerange parameter specifies the data based on time range.

Warning

timerange is prior than timebin, do not use timerange when timebin=’all’ is desired.

datacolumn (default : ‘float_data’)

If ‘float_data’ does not exist, ‘data is used instead.

Examples
sdtimeaverage(infile='sd_data.ms', outfile='sd_data_TimeAve.ms')
sdtimeaverage(infile='sd_data.ms', datacolumn='float_data', outfile='sd_data_TimeAve.ms')
sdtimeaverage(infile='sd_data.ms', datacolumn='float_data', timebin='all', outfile='sd_data_TimeAve.ms')
Development

No additional development details

Parameter Details

Detailed descriptions of each function parameter

infile (path) - name of input SD dataset
datacolumn (string='float_data') - name of data column to be used [“data”, “float_data”, or “corrected_data”]
field (string='') - select data by field IDs and names, e.g. “3C2*” (“”=all)
spw (string='') - select data by spectral windows and channels, e.g. “3,5,7” (“”=all)
timerange (string='') - select data by time range, e.g. “09:14:0~09:54:0” (“”=all) (see examples in help)
scan (string='') - select data by scan numbers, e.g. “21~23” (“”=all)
antenna (string='') - antenna IDs to be averaged over, e.g. “PM03” (“”=all)
timebin (string='all') - bin width for time averaging.
timespan (string='scan') - span across scan, state or both.
outfile (string='') - name of output file