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8.2.1.16 sdstat
Keyword arguments:  
infile -- name of input SD dataset  
        default: none - must input file name  
        example: ’mysd.asap’  
                 See sdreduce for allowed formats.  
antenna -- antenna name or id (only effective for MS input).  
fluxunit -- units for line flux  
        options: (str) ’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)  
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  
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 field, scanlist, and pollist  
pollist -- list of polarization id numbers to select  
        default: [] (use all pols)  
        example: [1]  
        this selection is in addition to field, scanlist, and iflist  
masklist -- list of mask regions to INCLUDE in stats  
        default: [] (whole spectrum)  
        example: [4000,4500] for one region  
                 [[1000,3000],[5000,7000]]  
                 these must be pairs of [lo,hi] boundaries  
invertmask -- invert mask (EXCLUDE masklist instead)  
        options: (bool) True,False  
        default: false  
interactive -- determines interactive masking  
        options: (bool) True,False  
        default: False  
        example: interactive=True allows adding and deleting mask  
                 regions by drawing rectangles on the plot with mouse.  
                 Draw a rectangle with LEFT-mouse to ADD the region to  
                 the mask and with RIGHT-mouse to DELETE the region.  
outfile -- name of output file for line statistics  
        default: ’’ (no output statistics file)  
        example: ’stat.txt’  
format -- format string to print statistic values  
        default: ’3.3f’  
overwrite -- overwrite the statistics file if already exists  
        options: (bool) True,False  
        default: False  
 
-------------------------------------------------------------------  
        Returns: a Python dictionary of line statistics  
           keys: ’rms’,’stddev’,’max’,’min’,’max_abscissa’,  
                 ’min_abscissa’,’sum’,’median’,’mean’,’totint’,’eqw’  
        example: xstat=sdstat(); print "rms = ",xstat[’rms’]  
                 these can be used for testing in scripts or  
                 for regression  
 
                 ’max_abscissa’ and ’min_abscissa’ refer to the abscissa  
                 (channel/frequency/velocity) of max and min intensity.  
                 ’totint’ is the integrated intensity (sum*dx)  
                 where dx is the abscissa interval in ’specunit’.  
                 ’eqw’ is equivalent width (totint/mag) where mag  
                 is either max or min depending on which has  
                 greater magnitude.  
                 Note that ’max_abscissa’, ’min_abscissa’, ’totint’  
                 and ’eqw’ are quantities (python dictionaries with  
                 keys, ’unit’ and ’value’).  

DESCRIPTION:

Task sdstat computes basic statistics (rms,mean,median,sum) for single-dish spectra. It assumes that the spectra have been calibrated. Furthermore, it assumes that any time and channel averaging/smoothing has also already been done as there are no controls for these. Note that you can run sdreduce with calmode=’none’ and do selection, writing out a new scantable. The calculated statistics are written into a file specified by outfile. Interactive mask specification is possible with interactive=True. Integrated intensity will be shown on the screen and will be included in the saved outfile (but not yet available in the returned dictionary).

Note that multiple scans and IFs can in principle be handled, but we recommend that you use scanlist, field, iflist, and pollist to give a single selection for each run.

See the sdcal description for information on the fluxunit conversion and the telescopeparm parameter. Also, see the sdcal description for note on GBT raw SDFITS format data.

WARNING: If you do have multiple scantable rows, then xstat values will be lists.


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