visstat.py

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#
# This file was generated using xslt from its XML file
#
# Copyright 2009, Associated Universities Inc., Washington DC
#
import sys
import os
from  casac import *
import string
from taskinit import casalog
#from taskmanager import tm
import task_visstat
def visstat(vis='', axis='amplitude', datacolumn='data', useflags=True, spw='', field='', selectdata=True, antenna='', uvrange='', timerange='', correlation='', scan='', array='', observation=''):

        """Displays statistical information from a measurement set, or from a measurement set selection

        This task returns statistical information about data in a measurement
        set.

        The following values are computed: mean value, sum of values,
        sum of squared values, median, median absolute deviation, quartile,
        minimum, maximum, variance, standard deviation, and root mean square.

        The following axes are supported: uvw, flag, weight, sigma, antenna1,
        antenna2, feed1, feed2, field_id, array_id, data_desc_id, flag_row,
        interval, scan, scan_number, time, weight_spectrum, amp, amplitude,
        phase, real, imag, imaginary, and uvrange.

        Optionally, the statistical information can be computed based only
        on a given subset of the measurement set.

        Note: If the MS consists of inhomogeneous data, for example several
        spectral windows each having a different number of channels, it may be
        necessary to use selection parameters to select a homogeneous subset of
        the MS, e.g. spw='2'.

        Keyword arguments:

        vis  --- Name of input visibility file
                  default: '', example: vis='my.ms'

        axis -- Which data to analyze.

                default: 'amplitude'
                axis='phase'
                axis='imag'
                axis='scan_number'
                axis='flag'

                The phase of a complex number is in radians in the range [-pi; pi[.


        datacolumn -- Which data column to use for complex data.
                default: 'data'
                datacolumn='data'
                datacolumn='corrected'
                datacolumn='model'

        useflags -- Take MS flags into account?
                default: True
                useflag=False
                useflag=True
        If useflags=False, flagged values are included in the statistics.
        If useflags=True, any flagged values are not used in the statistics.

        spw -- Select data based on spectral window and channels
                default: '' (all); example: spw='1'
                spw='<2' #spectral windows less than 2
                spw='>1' #spectral windows greater than 1
                spw='0:0~10' # first 10 channels from spw 0
                spw='0:0~5;56~60' # multiple separated channel chunks.

        field -- Select data based on field id(s) or name(s)
                default: '' (all); example: field='1'
                field='0~2' # field ids inclusive from 0 to 2
                field='3C*' # all field names starting with 3C

        selectdata -- Other data selection parameters
                default: True
        antenna -- Select data based on baseline
                default: '' (all); example: antenna='5&6' baseline 5-6
                antenna='5&6;7&8' #baseline 5-6 and 7-8
                antenna='5' # all baselines with antenna 5
                antenna='5,6' # all baselines with antennas 5 and 6
        correlation -- Correlation types
                default: '' (all);
                example: correlation='RR LL'
        uvrange -- Select data within uvrange (default units meters)
                default: '' (all); example:
                uvrange='0~1000klambda'; uvrange from 0-1000 kilo-lambda
                uvrange='>4klambda';uvranges greater than 4 kilo-lambda
                uvrange='0~1000km'; uvrange in kilometers
        timerange  -- Select data based on time range:
                default = '' (all); example,
                timerange = 'YYYY/MM/DD/hh:mm:ss~YYYY/MM/DD/hh:mm:ss'
                Note: YYYY/MM/DD can be dropped as needed:
                timerange='09:14:0~09:54:0' # this time range
                timerange='09:44:00' # data within one integration of time
                timerange='>10:24:00' # data after this time
                timerange='09:44:00+00:13:00' #data 13 minutes after time
        scan -- Select data based on scan number
                default: '' (all); example: scan='>3'
        array -- Selection based on the antenna array
        observation -- Selection by observation ID(s).
                       default: '' (all); example: observation='1~3'


        """

#
#    The following is work around to avoid a bug with current python translation
#
        mytmp = {}

        mytmp['vis'] = vis
        mytmp['axis'] = axis
        mytmp['datacolumn'] = datacolumn
        mytmp['useflags'] = useflags
        mytmp['spw'] = spw
        mytmp['field'] = field
        mytmp['selectdata'] = selectdata
        mytmp['antenna'] = antenna
        mytmp['uvrange'] = uvrange
        mytmp['timerange'] = timerange
        mytmp['correlation'] = correlation
        mytmp['scan'] = scan
        mytmp['array'] = array
        mytmp['observation'] = observation
        pathname='file:///'+os.environ.get('CASAPATH').split()[0]+'/share/xml/'
        trec = casac.utils().torecord(pathname+'visstat.xml')

        casalog.origin('visstat')
        if trec.has_key('visstat') and casac.utils().verify(mytmp, trec['visstat']) :
            result = task_visstat.visstat(vis, axis, datacolumn, useflags, spw, field, selectdata, antenna, uvrange, timerange, correlation, scan, array, observation)

        else :
          result = False
        return result