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0.1.78 oldsplit

Requires:

Synopsis
Create a visibility subset from an existing visibility set

Description

T H I S T A S K I S D E P R E C A T E D I T W I L L B E R E M O V E D S O O N

Oldsplit is the general purpose program to make a new data set that is a subset or averaged form of an existing data set. General selection parameters are included, and one or all of the various data columns (DATA, LAG_DATA and/or FLOAT_DATA, and possibly MODEL_DATA and/or CORRECTED_DATA) can be selected.

Oldsplit is often used after the initial calibration of the data to make a smaller measurement set with only the data that will be used in further flagging, imaging and/or self-calibration. Oldsplit can average over frequency (channels) and time (integrations).



Arguments





Inputs

vis

Name of input measurement set

allowed:

string

Default:

outputvis

Name of output measurement set

allowed:

string

Default:

datacolumn

Which data column(s) to Oldsplit out

allowed:

string

Default:

corrected

field

Select field using ID(s) or name(s)

allowed:

any

Default:

variant

spw

Select spectral window/channels

allowed:

any

Default:

variant

width

Number of channels to average to form one output channel

allowed:

any

Default:

variant 1

antenna

Select data based on antenna/baseline

allowed:

any

Default:

variant

timebin

Bin width for time averaging

allowed:

string

Default:

0s

timerange

Select data by time range

allowed:

string

Default:

scan

Select data by scan numbers

allowed:

string

Default:

intent

Select data by scan intents

allowed:

string

Default:

array

Select (sub)array(s) by array ID number

allowed:

string

Default:

uvrange

Select data by baseline length

allowed:

string

Default:

correlation

Select correlations

allowed:

any

Default:

variant

observation

Select by observation ID(s)

allowed:

any

Default:

variant

combine

Let time bins span changes in scan and/or state

allowed:

any

Default:

variant

keepflags

If practical, keep *completely flagged rows* instead of dropping them.

allowed:

bool

Default:

True

keepmms

If the input is a multi-MS, make the output one, too. (experimental)

allowed:

bool

Default:

False

Example

 
 
        Keyword arguments:  
        vis -- Name of input visibility file  
                default: none; example: vis=’ngc5921.ms’  
        outputvis -- Name of output visibility file  
                default: none; example: outputvis=’ngc5921_src.ms’  
 
        datacolumn -- Which data column to split out  
                default=’corrected’; example: datacolumn=’data’  
                Options: ’data’, ’model’, ’corrected’, ’all’,  
                ’float_data’, ’lag_data’, ’float_data,data’, and  
                ’lag_data,data’.  
                N.B.: ’all’ = whichever of the above that are present.  
                Otherwise the selected column will go to DATA (or  
                FLOAT_DATA) in the output.  
                Splitting with the default datacolumn=’corrected’  
                before clean is normally required for self-calibration!  
 
        --- Data Selection (see help par.selectdata for more detailed  
            information)  
 
        field -- Select field using field id(s) or field name(s).  
                  [run listobs to obtain the list id’s or names]  
               default: ’’=all fields If field string is a non-negative  
               integer, it is assumed to be a field index  
               otherwise, it is assumed to be a field name  
               field=’0~2’; field ids 0,1,2  
               field=’0,4,5~7’; field ids 0,4,5,6,7  
               field=’3C286,3C295’; fields named 3C286 and 3C295  
               field = ’3,4C*’; field id 3, all names starting with 4C  
        spw -- Select spectral window/channels  
               default: ’’=all spectral windows and channels  
               spw=’0~2,4’; spectral windows 0,1,2,4 (all channels)  
               spw=’<2’;  spectral windows less than 2 (i.e. 0,1)  
               spw=’0:5~61’; spw 0, channels 5 to 61  
               spw=’0,10,3:3~45’; spw 0,10 all channels, spw 3 - chans 3 to 45.  
               spw=’0~2:2~6’; spw 0,1,2 with channels 2 through 6 in each.  
               spw = ’*:3~64’  channels 3 through 64 for all sp id’s  
                       spw = ’ :3~64’ will NOT work.  
               Oldsplit does not support multiple channel ranges per spectral  
               window (’;’) because it is not clear whether to keep the ranges  
               in the original spectral window or make a new spectral window  
               for each additional range.  
width -- Defines the number of channel to average to form the one  
         output channel.  
 default: ’1’ => no channel averaging  
 example: width=[2,3] => average 2 channels of 1st  
          spectral window selected and 3 in the second one.  
        antenna -- Select data based on antenna/baseline  
               default: ’’ (all)  
                Non-negative integers are assumed to be antenna indices, and  
                anything else is taken as an antenna name.  
 
                Examples:  
                antenna=’5&6’: baseline between antenna index 5 and index 6.  
                antenna=’VA05&VA06’: baseline between VLA antenna 5 and 6.  
                antenna=’5&6;7&8’: baselines 5-6 and 7-8  
                antenna=’5’: all baselines with antenna 5  
                antenna=’5,6,10’: all baselines including antennas 5, 6, or 10  
                antenna=’5,6,10&’: all baselines with *only* antennas 5, 6, or  
                                       10.  (cross-correlations only.  Use &&  
                                       to include autocorrelations, and &&&  
                                       to get only autocorrelations.)  
                antenna=’!ea03,ea12,ea17’: all baselines except those that  
                                           include EVLA antennas ea03, ea12, or  
                                           ea17.  
        timebin -- Interval width for time averaging.  
                   default: ’0s’ or ’-1s’ (no averaging)  
                   example: timebin=’30s’  
                            ’10’ means ’10s’  
        timerange -- Select data based on time range:  
               default = ’’ (all); examples,  
               timerange = ’YYYY/MM/DD/hh:mm:ss~YYYY/MM/DD/hh:mm:ss’  
               Note: if YYYY/MM/DD is missing date, timerange defaults to the  
               first day in the dataset  
               timerange=’09:14:0~09:54:0’ picks 40 min on first day  
               timerange=’25:00:00~27:30:00’ picks 1 hr to 3 hr 30min  
               on next day  
               timerange=’09:44:00’ data within one integration of time  
               timerange=’>10:24:00’ data after this time  
        array -- (Sub)array number range  
            default: ’’=all  
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  
scan -- Scan number range  
            default: ’’=all  
        intent -- Select by scan intent (state).  Case sensitive.  
            default: ’’ = all  
            Examples:  
            intent = ’CALIBRATE_ATMOSPHERE_REFERENCE’  
            intent = ’calibrate_atmosphere_reference’.upper() # same as above  
            # Select states that include one or both of CALIBRATE_WVR.REFERENCE  
            # or OBSERVE_TARGET_ON_SOURCE.  
            intent = ’CALIBRATE_WVR.REFERENCE, OBSERVE_TARGET_ON_SOURCE’  
        correlation -- Select correlations, e.g. ’rr, ll’ or [’XY’, ’YX’].  
                       default ’’ (all).  
        observation -- Select by observation ID(s).  
                       default: ’’ = all  
        combine -- Let time bins span changes in scan and/or state.  
                   default = ’’ (separate time bins by both of the above)  
                   combine = ’scan’: Can be useful when the scan number  
                                     goes up with each integration,  
                                     as in many WSRT MSes.  
                   combine = [’scan’, ’state’]: disregard scan and state  
                                                numbers when time averaging.  
                   combine = ’state,scan’: Same as above.  
        keepflags -- If practical, keep completely flagged rows instead of  
                     dropping them.  This has absolutely no effect on averaging  
                     calculations, or partially flagged rows.  All of the  
                     channels and correlations of a row must be flagged for it  
                     to be droppable, and a row must be well defined to be  
                     keepable.  The latter condition means that this option has  
                     no effect on time averaging - in that case fully flagged  
                     rows are automatically omitted.  Regardless of this  
                     parameter, flagged data is never included in averaging  
                     calculations.  
 
                     The only time keepflags matters is if  
                     1. the input MS has some completely flagged rows  
                     and  
                     2. time averaging is not being done.  
 
                     Then, if keepflags is False, the completely flagged rows  
                     will be omitted from the output MS.  Otherwise, they will  
                     be included (subject to the selection parameters).  
 
        keepmms -- If true and the input is a multi-MS, make the output one, too.  
           Otherwise, the output will be a normal MS without partitioning.  
   (experimental)  
                   Default: False  
 


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