casa: task_conjugatevis.py Source File

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00001 import os
00002 from taskinit import *
00003 
00004 def conjugatevis(vis,spwlist=[],outputvis="",overwrite=False):
00005         """:
00006         Change the sign of the phases in all visibility columns
00007 
00008         Keyword arguments:
00009         vis -- Name of input visibility file
00010                 default: none; example='3C273XC1.ms'
00011         spwlist -- Select spectral window
00012                 default: [] all spws will be conjugated; example: spw=[1,2]
00013         outputvis -- name of output visibility file
00014                 default: 'conjugated_'+vis; example= 'conjugated.ms'
00015         overwrite -- Overwrite the outputvis if it exists
00016                 default=False; example: overwrite=True
00017 
00018         """
00019 
00020         #Python script
00021         try:
00022                 casalog.origin('conjugatevis')
00023                 myddlist = []
00024                 tb.open(vis+'/SPECTRAL_WINDOW')
00025                 maxspw = tb.nrows()-1
00026                 tb.close()
00027                 if (type(spwlist)==type(1)):
00028                         spwlist = [spwlist]
00029                 elif(spwlist==None or spwlist==[] or spwlist==""):
00030                         spwlist = []
00031                         casalog.post("Will conjugate visibilities for all spws.", 'INFO')
00032                 if not spwlist==[]:
00033                         try:
00034                                 tb.open(vis+'/DATA_DESCRIPTION')
00035                                 for k in spwlist:
00036                                         if (k<-1 or k>maxspw):
00037                                                 raise Exception, "Error: max valid spw id is "+str(maxspw)
00038                                                 raise
00039                                         else:
00040                                                 for j in range(0,tb.nrows()):
00041                                                         if(tb.getcell("SPECTRAL_WINDOW_ID",j)==k and not (j in myddlist)):
00042                                                                 myddlist = myddlist + [j]
00043                                 #end for k
00044                                 tb.close()
00045                                 casalog.post('DATA_DESC_IDs to process: '+str(myddlist), 'INFO')
00046                         except:
00047                                 raise Exception, 'Error reading DATA_DESCRIPTION table'
00048                 #endif
00049                 outname = 'conjugatedvis_'+vis
00050                 if not outputvis=="":
00051                         if((type(outputvis)!=str) or (len(outputvis.split()) < 1)):
00052                                 raise Exception, 'parameter outputvis is invalid'
00053                         outname = outputvis
00054                 if not overwrite and os.path.exists(outname):
00055                         raise Exception, 'outputvis '+outname+' exists and you did not permit overwrite'
00056                 os.system('rm -rf '+outname)
00057                 os.system('cp -R '+vis+' '+outname)
00058                 tb.open(outname, nomodify=False)
00059                 if tb.iswritable():
00060                         if(spwlist==None):
00061                                 for colname in [ 'DATA', 'CORRECTED_DATA', 'FLOAT_DATA' ]:
00062                                         if colname in tb.colnames():
00063                                                 casalog.post('Conjugating '+str(colname), 'INFO')
00064                                                 for i in xrange(0,tb.nrows()):
00065                                                         a = tb.getcell(colname, i)
00066                                                         a = a.conjugate()
00067                                                         tb.putcell(colname, i, a)
00068                         else:
00069                                 for colname in [ 'DATA', 'CORRECTED_DATA', 'FLOAT_DATA' ]:
00070                                         if colname in tb.colnames():
00071                                                 casalog.post('Conjugating '+str(colname), 'INFO')
00072                                                 for i in xrange(0,tb.nrows()):
00073                                                         if(tb.getcell("DATA_DESC_ID",i) in myddlist):
00074                                                                 a = tb.getcell(colname, i)
00075                                                                 a = a.conjugate()
00076                                                                 tb.putcell(colname, i, a)
00077                         #endif
00078                         tb.flush()
00079                         tb.close()
00080                         casalog.post('Created '+str(outname), 'INFO')
00081                 else:
00082                         tb.close()
00083                         casalog.post('Cannot write to output MS '+str(outname), 'WARN')
00084 
00085         except Exception, instance:
00086                 tb.close()
00087                 print '*** Error ***', instance
00088                 raise Exception, instance
00089 
00090