Known Issues, Problems, Deficiencies and Features

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8.5 Known Issues, Problems, Deficiencies and Features

The Single-Dish calibration and analysis package within CASA is still very much under development. Not surprisingly, there are a number of issues with ASAP and the SDtasks that are known and under repair. Some of these are non-obvious ”features” by the way ASAP and sd are implemented, or limitations of the current Python tasking environment. Some are functions that have yet to be implemented. These currently include:

sd.plotter
The method, sd.plotter.set_range() sets the same range for multiple panels, while we would like it to be able to set the range for each independently, including the default ranges.
The sd.plotter object remembers things throughout the session and thus can easily get confused. For example, one must reset the range sd.plotter.set_range() if set manually. This behaviour is not always expected, but is a consequence of having sd.plotter be its own object that is fed data and commands.
Eventually we would like the capability to interactively set things using the plots, like select frequency ranges, identify lines, start fitting.
sd.selector
The selector object only allows one selection of each type. It would be nice to be able to make a union of selections (without resorting to query) for the set_name. Note that the others like scans and IFs work off lists, which is fine. We should make set_name work off lists of names.
sd.scantable
The scantable.verbosesummary asaprc parameter (e.g. in sd.rcParams) does nothing.
GBT data has an undefined parameter fluxunit (’’ that should be ’K’), an incorrect freqframe (’LSRK’ that is is really ’TOPO’), and reference frequency (set to that of the first IF only).
The sd.scantable.freq_align does not yet work correctly.
sd general issues
There should be a sdhelp equivalent of toolhelp and tasklist for the sd tools and tasks.
The current output of ASAP is verbose and controlled by setting sd.rcParams[’verbose’]=False (or True). We will make some of the output less cryptic.
We will strip off leading and trailing whitespace on string parameters.
SDtasks general issues
The SDtasks work with files saved onto disk in one of the scantable supported formats. It might be useful to work with scantables in memory (passing the objects) but this would require changes to the tasking system. Note that this behavior is consistent throughout the casapy tasks.
sdcal (and sdreduce)
averageall=True is still experimental since the test was insufficient because of a lack of test data.
sdfit
Only way to handle multi-IFs is to set fitmode=’auto’ (linefinder is applied for each spectra and derives initial guesses). For fitmode=’list’, there are no way to give initial guesses for each IFs by hand.
sdplot
Only handles the included JPL line catalog. Also, see sd.plotter issues above.
GBT raw SDFITS data
The SDtasks and sd.scantable are able to handle GBT raw SDFITS data format (version 1.3) data since the data filler is available. However, the functionality is not well tested yet, so that there may be unknown bugs.

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