task_polcal.py

Go to the documentation of this file.

import os
import numpy as np
from taskinit import *

def polcal(vis=None,caltable=None,
           field=None,spw=None,intent=None,
           selectdata=None,timerange=None,uvrange=None,antenna=None,scan=None,
           observation=None, msselect=None,
           solint=None,combine=None,preavg=None,refant=None,minblperant=None,minsnr=None,
           poltype=None,smodel=None,append=None,
           gaintable=None,gainfield=None,interp=None,spwmap=None,
           gaincurve=None,opacity=None):

        #Python script
        casalog.origin('polcal')

        try: 
                if ((type(vis)==str) & (os.path.exists(vis))):
                        cb.open(filename=vis,compress=False,addcorr=False,addmodel=False)
                else:
                        raise Exception, 'Visibility data set not found - please verify the name'

                # Do data selection according to selectdata
                if (selectdata):
                        # pass all data selection parameters in as specified
                        cb.selectvis(time=timerange,spw=spw,scan=scan,field=field,
                                     intent=intent, observation=str(observation),
                                     baseline=antenna,uvrange=uvrange,chanmode='none',
                                     msselect=msselect);
                else:
                        # selectdata=F, so time,scan,baseline,uvrange,msselect=''
                        # using spw and field specifications only
                        cb.selectvis(time='',spw=spw,scan='',field=field,intent=intent,
                                     baseline='',uvrange='',chanmode='none',
                                     observation='', msselect='')

                # set the model, if specified
                if (len(smodel)>0):
                        cb.setptmodel(smodel);

                # Arrange apply of existing other calibrations 
                # First do the existing cal tables...
                ngaintab = 0;
                if (gaintable!=['']):
                        ngaintab=len(gaintable)
                ngainfld = len(gainfield)
                nspwmap = len(spwmap)
                ninterp = len(interp)

                # handle list of list issues with spwmap
                if (nspwmap>0):
                        if (type(spwmap[0])!=list):
                                # first element not a list, only one spwmap specified
                                # make it a list of list
                                spwmap=[spwmap];
                                nspwmap=1;

                for igt in range(ngaintab):
                        if (gaintable[igt]!=''):

                                # field selection is null unless specified
                                thisgainfield=''
                                if (igt<ngainfld):
                                        thisgainfield=gainfield[igt]
                                        
                                # spwmap is null unless specifed
                                thisspwmap=[-1]
                                if (igt<nspwmap):
                                        thisspwmap=spwmap[igt];

                                # interp is 'linear' unless specified
                                thisinterp='linear'
                                if (igt<ninterp):
                                        if (interp[igt]==''):
                                                interp[igt]=thisinterp
                                        thisinterp=interp[igt];

                                cb.setapply(t=0.0,table=gaintable[igt],field=thisgainfield,
                                            calwt=True,spwmap=thisspwmap,interp=thisinterp)
                
                # ...and now the specialized terms
                # (BTW, interp irrelevant for these, since they are evaluated)

                # opacity (if non-trivially specified and any >0.0)
                opacarr=np.array(opacity)   # as numpy array for uniformity
                if (np.sum(opacarr)>0.0):
                        # opacity transmitted as a list in all cases
                        cb.setapply(type='TOPAC',t=-1,opacity=opacarr.tolist(),calwt=True)

                if gaincurve: cb.setapply(type='GAINCURVE',t=-1,calwt=True)


                # D-terms require parallactic angle
                cb.setapply(type='P')

                # Set up for solving: 
                phaseonly=False
                cb.setsolve(type=poltype,t=solint,combine=combine,preavg=preavg,refant=refant,
                            minblperant=minblperant,solnorm=False,minsnr=minsnr,table=caltable,
                            apmode='ap',phaseonly=phaseonly,append=append)

                cb.solve()
                cb.close()

        except Exception, instance:
                print '*** Error ***',instance
                cb.close()
                raise Exception, instance