pipeline.hifa.cli.hifa_antpos

pipeline.hifa.cli.hifa_antpos = <pipeline.hifa.cli.hifa_antpos._hifa_antpos object>

hifa_antpos —- Derive an antenna position calibration table

The hifa_antpos task corrects the antenna positions recorded in the ASDMs using updated antenna position calibration information determined after the observation was taken.

Corrections can be input by hand, read from a file on disk, or in the future by querying an ALMA database service.

The antenna positions file is in ‘csv’ format containing 6 comma-delimited columns as shown below. The default name of this file is ‘antennapos.csv’.

Contents of example ‘antennapos.csv’ file:

ms,antenna,xoffset,yoffset,zoffset,comment uid___A002_X30a93d_X43e.ms,DV11,0.000,0.010,0.000,”No comment” uid___A002_X30a93d_X43e.dup.ms,DV11,0.000,-0.010,0.000,”No comment”

The corrections are used to generate a calibration table which is recorded in the pipeline context and applied to the raw visibility data, on the fly to generate other calibration tables, or permanently to generate calibrated visibilities for imaging.

If pipeline mode is ‘getinputs’ then None is returned. Otherwise the results object for the pipeline task is returned.

Note: the hm_antpos ‘online’ option will be implemented when the observing system provides an antenna position determination service.

——— parameter descriptions ———————————————

vis List of input MeasurementSets. Defaults to the list of

MeasurementSets specified in the pipeline context.

Example: vis=[‘ngc5921.ms’]

caltable List of names for the output calibration tables. Defaults

to the standard pipeline naming convention.

Example: caltable=[‘ngc5921.gcal’]

hm_antpos Heuristics method for retrieving the antenna position

corrections. The options are ‘online’ (not yet implemented), ‘manual’, and ‘file’.

Example: hm_antpos=’manual’

antenna The list of antennas for which the positions are to be corrected

if hm_antpos is ‘manual’.

Example: antenna=’DV05,DV07’

offsets The list of antenna offsets for each antenna in ‘antennas’. Each

offset is a set of 3 floating point numbers separated by commas, specified in the ITRF frame.

Example: offsets=[0.01, 0.02, 0.03, 0.03, 0.02, 0.01]

antposfile The file(s) containing the antenna offsets. Used if hm_antpos

is ‘file’.

pipelinemode The pipeline operating mode. In ‘automatic’ mode the pipeline

determines the values of all context defined pipeline inputs automatically. In interactive mode the user can set the pipeline context defined parameters manually. In ‘getinputs’ mode the user can check the settings of all pipeline parameters without running the task.

dryrun Run the commands (True) or generate the commands to be run but

do not execute (False).

acceptresults Automatically accept the results of the task into the pipeline context (True)

or reject them (False).

——— examples ———————————————————–

1. Correct the position of antenna 5 for all the visibility files in a single pipeline run:

hifa_antpos(antenna=’DV05’, offsets=[0.01, 0.02, 0.03])

2. Correct the position of antennas for all the visibility files in a single pipeline run using antenna positions files on disk. These files are assumed to conform to a default naming scheme if ‘antposfile’ is unspecified by the user:

hifa_antpos(hm_antpos=’file’, antposfile=’myantposfile.csv’)