Changeset 1650

Timestamp:

10/21/09 13:54:00 (15 years ago)

Author:

Kana Sugimoto

Message:

New Development: Yes

JIRA Issue: Yes (CAS-1441)

Ready to Release: Yes

Interface Changes: Yes

What Interface Changed: A new method 'splitant' is created.

Note the method is only available from CASA.

Test Programs: sd.splitant('INPUT.ms',outprefix='outfile')

Put in Release Notes: Yes

Module(s): None

Description:

A new method 'splitant' is added. This method is to split a measurement set
containing multiple antenna by antenna and output them as scantables.
The list of scantable names is returned.
Note this method calls CASA table tools and only available from CASA.

File:

• branches/alma/python/asapmath.py (modified) (2 diffs)

branches/alma/python/asapmath.py

@@ -901 +901 @@
         scannos:       list of scan number
         calmode:       calibration mode
+
         verify:        verify calibration     
     """
@@ -909 +910 @@
     scal = scantable( stm.cwcal( ssub, calmode, antname ) )
     return scal
+
+### Start mod: 2009.10.16 kana ###
+def splitant(filename, outprefix='',overwrite=False):
+    """
+    Split Measurement set by antenna name, save data as a scantables,
+    and return a list of filename.
+    Notice this method can only be available from CASA. 
+    Prameter
+       filename:    the name of Measurement set to be read. 
+       outprefix:   the prefix of output scantable name.
+                    the names of output scantable will be
+                    outprefix.antenna1, outprefix.antenna2, ....
+       overwrite    If the file should be overwritten if it exists.
+                    The default False is to return with warning
+                    without writing the output. USE WITH CARE.
+                    
+    """
+    # Import the table toolkit from CASA
+    try:
+        import casac
+    except ImportError:
+        if rcParams['verbose']:
+            #print "failed to load casa"
+            print_log()
+            asaplog.push("failed to load casa")
+            print_log('ERROR')
+        else: raise
+        return False
+    try:
+        tbtool = casac.homefinder.find_home_by_name('tableHome')
+        tb = tbtool.create()
+        tb2 = tbtool.create()
+    except:
+        if rcParams['verbose']:
+            #print "failed to load a table tool:\n", e
+            print_log()
+            asaplog.push("failed to load table tool")
+            print_log('ERROR')
+        else: raise
+        return False
+    # Check the input filename
+    if isinstance(filename, str):
+        import os.path
+        filename = os.path.expandvars(filename)
+        filename = os.path.expanduser(filename)
+        if not os.path.exists(filename):
+            s = "File '%s' not found." % (filename)
+            if rcParams['verbose']:
+                print_log()
+                asaplog.push(s)
+                print_log('ERROR')
+                return
+            raise IOError(s)
+        # check if input file is MS
+        if not os.path.isdir(filename) \
+               or not os.path.exists(filename+'/ANTENNA') \
+               or not os.path.exists(filename+'/table.f1'): 
+            s = "File '%s' is not a Measurement set." % (filename)
+            if rcParams['verbose']:
+                print_log()
+                asaplog.push(s)
+                print_log('ERROR')
+                return
+            raise IOError(s)
+    else:
+        s = "The filename should be string. "
+        if rcParams['verbose']:
+            print_log()
+            asaplog.push(s)
+            print_log('ERROR')
+            return
+        raise TypeError(s)
+    # Check out put file name
+    outname=''
+    if len(outprefix) > 0: prefix=outprefix+'.'
+    # Now do the actual splitting.
+    outfiles=[]
+    tmpms="temp_antsplit.ms"
+    if os.path.exists(tmpms):
+        ans=raw_input('Temporal file '+tmpms+' exists. Delete it and continue? [y/N]: ')
+        if ans.upper() == 'Y':
+            os.system('rm -rf '+tmpms)
+            asaplog.push('The file '+tmpms+' deleted.')
+        else:
+            asaplog.push('Exit without splitting.')
+            return
+    tb.open(tablename=filename+'/ANTENNA',nomodify=True)
+    nant=tb.nrows()
+    antnames=tb.getcol('NAME',0,nant,1)
+    antpos=tb.getcol('POSITION',0,nant,1).transpose()
+    tb.close()
+    tb.open(tablename=filename,nomodify=True)
+    ant1=tb.getcol('ANTENNA1',0,-1,1)
+    for antid in set(ant1):
+        qstr="ANTENNA1 == "+str(antid)
+        stab = tb.queryC(qstr)
+        ctab = stab.copy(tmpms,deep=True)
+        stab.close()
+        ctab.close()
+        scan=scantable(tmpms,False)
+        outname=prefix+antnames[antid]+'.asap'
+        scan.save(outname,format='ASAP',overwrite=overwrite)
+        # Modify scantable header
+        tb2.open(tablename=outname,nomodify=False)
+        tb2.putkeyword(keyword='AntennaName',value=antnames[antid])
+        tb2.putkeyword(keyword='AntennaPosition',value=antpos[antid])
+        tb2.flush()
+        tb2.close()
+        del scan, ctab, stab
+        outfiles.append(outname)
+    tb.close()
+    del tb, tb2
+    os.system('rm -rf '+tmpms)
+    return outfiles
+### End mod ######################