smoothcal

smoothcal(vis, tablein, caltable='', field='', smoothtype='median', smoothtime=60.0, ratesmooth=False)[source]

Smooth calibration solution(s) derived from one or more sources

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

Parameters

vis (path) - Name of input visibility file (MS)
tablein (path) - Input calibration table
caltable (string=’’) - Output calibration table (overwrite tablein if unspecified)
field (stringVec=’’) - Field name list
smoothtype (string=’median’) - Smoothing filter to use
smoothtime ({double, int}=60.0) - Smoothing time (sec)
ratesmooth (bool=False) - EXPERIMENTAL rate aware smoothing

Description

The smoothcal task will smooth calibration solutions (most usefully ‘G’ or ‘T’) over a specified time interval to reduce noise and outliers. Flagged solutions will be unflagged and replaced with smoothed solutions if unflagged solutions are available within the smoothing window. Smoothing will be applied per field and per spw; these cannot be combined.

Parameter Descriptions

Input/output: vis, tablein, caltable

Specify the relevant MS in vis (for meta-info purposes; will someday deprecate), and the input calibration table in tablein. Specify the output (smoothed) calibration table name in caltable. If caltable is left unspecified, the input calibration table (tablein) will be overwritten with the smoothed result.

Selection: field

Specify the subset of fields to be smoothed in field. All fields wil be copied to the new calibration table, but only the specified fields will be smoothed.

Smoothing parameters: smoothtype, smoothtime

Specify the smoothing type, ‘mean’ or ‘median’ in smoothtype. The timescale (the boxcar width) over which the smooth operation is applied should be specified in smoothtime, in seconds. Amplitude and phase will each be (separately) smoothed with the specified smoothtype and smoothtime. Currently, it is not possible to smooth amplitude and phase with different values of smoothtype or smoothtime.

Examples

To smooth the caltable ‘n4826_16apr.gcal’ on a 3-hour timescale with a boxcar mean:

smoothcal(vis='n4826_16apr.ms',
          tablein='n4826_16apr.gcal',
          caltable='n4826_16apr.smoothcal',
          smoothtime=7200.,
          smoothtype='mean')

Results can be plotted with plotms.

Development: No additional development details

Parameter Details: Detailed descriptions of each function parameter

vis (path) - Name of input visibility file (MS)

tablein (path) - Input calibration table

caltable (string='') - Output calibration table (overwrite tablein if unspecified)

field (stringVec='') - Field name list

smoothtype (string='median') - Smoothing filter to use

smoothtime ({double, int}=60.0) - Smoothing time (sec)

ratesmooth (bool=False) - Use rate aware smoothing. This is an experimental feature