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8.2.1.1 sdcal
Keyword arguments:  
infile -- name of input SD dataset  
antenna -- antenna name or id (only effective for MS input).  
fluxunit -- units for line flux  
        options: ’K’,’Jy’,’’  
        default: ’’ (keep current fluxunit)  
        WARNING: For GBT data, see description below.  
 
    >>> fluxunit expandable parameter  
         telescopeparm -- the telescope characteristics  
                 options: (str) name or (list) list of gain info  
                 default: ’’ (none set)  
                 example: if telescopeparm=’’, it tries to get the telescope  
                          name from the data.  
                          Full antenna parameters (diameter,ap.eff.) known  
                          to ASAP are  
                          ’ATPKSMB’, ’ATPKSHOH’, ’ATMOPRA’, ’DSS-43’,  
                          ’CEDUNA’,’HOBART’. For GBT, it fixes default fluxunit  
                          to ’K’ first then convert to a new fluxunit.  
                          telescopeparm=[104.9,0.43] diameter(m), ap.eff.  
                          telescopeparm=[0.743] gain in Jy/K  
                          telescopeparm=’FIX’ to change default fluxunit  
                          see description below  
 
specunit -- units for spectral axis  
        options: (str) ’channel’,’km/s’,’GHz’,’MHz’,’kHz’,’Hz’  
        default: ’’ (=current)  
        example: this will be the units for masklist  
frame -- frequency frame for spectral axis  
        options: (str) ’LSRK’,’REST’,’TOPO’,’LSRD’,’BARY’,  
                 ’GEO’,’GALACTO’,’LGROUP’,’CMB’  
        default: currently set frame in scantable  
        WARNING: frame=’REST’ not yet implemented  
doppler -- doppler mode  
        options: (str) ’RADIO’,’OPTICAL’,’Z’,’BETA’,’GAMMA’  
        default: currently set doppler in scantable  
calmode -- calibration mode  
        options: ’ps’,’nod’,’fs’,’fsotf’,’quotient’,’none’  
        default: ’none’  
        example: choose mode ’none’ if you have  
                 already calibrated and want to  
                 try averaging  
        WARNING: ’fsotf’ is not implemented yet  
scanlist -- list of scan numbers to process  
        default: [] (use all scans)  
        example: [21,22,23,24]  
        this selection is in addition to field, iflist, and pollist  
field -- selection string for selecting scans by name  
        default: ’’ (no name selection)  
        example: ’FLS3a*’  
        this selection is in addition to scanlist, iflist, and pollist  
iflist -- list of IF id numbers to select  
        default: [] (use all IFs)  
        example: [15]  
        this selection is in addition to scanlist, field, and pollist  
pollist -- list of polarization id numbers to select  
        default: [] (use all polarizations)  
        example: [1]  
        this selection is in addition to scanlist, field, and iflist  
channelrange -- channel range selection  
        default: [] (use all channel)  
        example: [0,5000]  
        Note that specified values are recognized as ’channel’  
        regardless of the value of specunit  
scanaverage -- average integrations within scans  
        options: (bool) True,False  
        default: False  
timeaverage -- average times for multiple scan cycles  
        options: (bool) True,False  
        default: False  
        example: if True, this happens after calibration  
 
    >>>timeaverage expandable parameter  
         tweight -- weighting for time average  
                 options: ’none’  
                          ’var’   (1/var(spec) weighted)  
                          ’tsys’  (1/Tsys**2 weighted)  
                          ’tint’  (integration time weighted)  
                          ’tintsys’  (Tint/Tsys**2)  
                          ’median’  ( median averaging)  
                 default: ’none’  
 
         averageall -- average multi-resolution spectra  
                       spectra are averaged by referring  
                       their frequency coverage  
                 default: False  
 
polaverage -- average polarizations  
        options: (bool) True,False  
        default: False  
 
    >>>polaverage expandable parameter  
         pweight -- weighting for polarization average  
                 options: ’none’  
                          ’var’  (1/var(spec) weighted)  
                          ’tsys’ (1/Tsys**2 weighted)  
                 default: ’none’  
 
tau -- atmospheric optical depth  
        default: 0.0 (no correction)  
verify -- verify the results of calibration. Only effective if  
          calmode is not ’none’.  
        options: (bool) True,False  
        default: False  
        WARNING: Currently this just asks whether you accept  
                 the displayed calibration and if not, continues  
                 without doing any calibration.  
outfile -- Name of output file  
        default: ’’ (<infile>_cal)  
outform -- format of output file  
        options: ’ASCII’,’SDFITS’,’MS’,’ASAP’  
        default: ’ASAP’  
        example: the ASAP format is easiest for further sd  
                 processing; use MS for CASA imaging.  
                 If ASCII, then will append some stuff to  
                 the outfile name  
overwrite -- overwrite the output file if already exists  
        options: (bool) True,False  
        default: False  
        WARNING: if outform=’ASCII’, this parameter is ignored  
plotlevel -- control for plotting of results  
        options: (int) 0=none, 1=some, 2=more, <0=hardcopy  
        default: 0 (no plotting)  
        example: plotlevel<0 as abs(plotlevel), e.g.  
                 -1 => hardcopy of final plot (will be named  
                 <outfile>_calspec.eps)  
        WARNING: be careful plotting in fsotf mode!

DESCRIPTION:

Task sdcal performs data selection, calibration for single-dish spectra. By setting calmode=’none’, one can run sdcal on already calibrated data, for further selection , averaging and atmospheric optical depth correction. To save the output spectra in a certain range of channels, you set the range in channelrange.

If you give multiple IFs in iflist, then your scantable will have multiple IFs by default. Averaging of multi-resolution (multi-IFs) spectra can be achieved by setting a sub-parameter in timeaverage, averageall, to True. It handles multi-IFs by selecting overlaps in frequency coverages and assigning new IFs in the output spectra.

ASAP recognizes the data of the ”AT” telescopes, but currently does not know about the GBT or any other telescope. This task does know about GBT. Telescope name is obtained from the data. If you wish to change the fluxunit (see below), by leaving the sub-parameter telescopeparm unset (telescopeparm=’’), it will use internal telescope parameters for flux conversion for the data from AT telescopes and it will use an approximate aperture efficiency conversion for the GBT data. If you give telescopeparm a list, then if the list has a single float it is assumed to be the gain in Jy/K, if two or more elements they are assumed to be telescope diameter (m) and aperture efficiency respectively.

Note that sdcal assumes that the fluxunit is set correctly in the data already. If not, then set telescopeparm=’FIX’ and it will set the default units to fluxunit without conversion. NOTE: If the data in infile is an ms from GBT and the default flux unit is missing, this task automatically fixes the default fluxunit to ’K’ before the conversion.

WARNING for the GBT raw SDFITS format data as input:
SDtasks are able to handle GBT raw SDFITS 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.

Notes:

R3.4 New Features:
This task has been renamed, and was previously called sdaverage.


More information about CASA may be found at the CASA web page

Copyright © 2010 Associated Universities Inc., Washington, D.C.

This code is available under the terms of the GNU General Public Lincense


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