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0.1.32 ft

Requires:

Synopsis
Insert a source model a visibility set:

Description

A source model (souce.model image) or components list is converted into model visibilities that is inserted into the MODEL_DATA column or alternatively is stored in the header of the MS to be served on the fly when requested. This is needed to use more complicated sources than setjy provides; e.g resolved source or off centered sources in gaincal. (Setjy will automatically make this ft step.)

The sources currently available are 3C48, 3C138, 3C147, 3C286 at 1.4, 5.0, 8.4, 15, 22, 43 GHz. Their location is site dependent. In Charlottesville and at the SOC, the models are in /usr/lib/casapy/data/nrao/VLA/CalModels.

Arguments





Inputs

vis

Name of input visibility file (MS)

allowed:

string

Default:

field

Field selection

allowed:

string

Default:

spw

Spw selection

allowed:

string

Default:

model

Name of input model image(s)

allowed:

any

Default:

variant

nterms

Number of terms used to model the sky frequency dependence

allowed:

int

Default:

1

reffreq

Reference frequency (e.g. ’1.5e+9’ or ’1.5GHz’)

allowed:

string

Default:

complist

Name of component list

allowed:

string

Default:

incremental

Add to the existing model visibility?

allowed:

bool

Default:

False

usescratch

If True predicted visibility is stored in MODEL_DATA column

allowed:

bool

Default:

False

Returns
void

Example

 
 
       A source model (souce.model image) or components list is converted into a  
       model visibility that is inserted into the MODEL_DATA column.  This is  
       needed to use resolved source in gaincal and in fluxscale.  
 
       Setjy will automatically make this ft step on the  
       sources currently available are 3C48, 3C138, 3C147, 3C286  
       at 1.4, 5.0, 8.4, 15, 22, 43 GHz.  Their location is site  
       dependent.  In Charlottesville and at the AOC, the models are  
       in /usr/lib(lib64)/casapy/data/nrao/VLA/CalModels.  
 
 
       Keyword arguments:  
       vis -- Name of input visibility file  
              default: none; example: vis=’ngc5921.ms’  
       field -- Field name list  
               default: ’’ ==> all  
               NOTE: BUT, only one source can be specified in a multi-source vis.  
               field = ’1328+307’  specifies source ’1328+307’  
               field = ’4’ specified field with index 4  
       spw -- Spw selection  
               default: spw = ’’ (all spw)  
       model -- Name of input model image  
               default: ’’ ==> None;  
               example: model=’/usr/lib/casapy/data/nrao/VLA/CalModels/3C286_X.im’  
               Note: The model visibilities are scaled from the model frequency  
                     to the observed frequency of the data.  
       nterms -- Number of terms used to model the sky frequency dependence  
                 default: 1  ==> one model image is required  
                 example : nterms=3  represents a 2nd order Taylor-polynomial in frequency  
                           and should be used in conjuction with coefficient model images as  
           model=[’xxx.model.tt0’,’xxx.model.tt1’, ’xxx.model.tt2’]  
             reffreq -- Reference-frequency about which this Taylor-expansion is defined.  
                default: ’’ ==> reads the reference frequency from the model image  
                        example : reffreq = ’1.5GHz’  
       complist -- Name of component list  
               default: None; ; example: complist=’test.cl’  
               component lists are difficult to make.  
       incremental -- Add model visibility to the existing model visibilties stored in the MS  
               default: False; example: incremental=True  
       usescratch  -- if True model visibilities will be stored in the scratch column  
                            MODEL_DATA; when false the model visibilities will be generated  
                            on the fly (this mode may save some disk space equivalent to  
    the volume of the observed data).  
                            default: False; example usescratch=True  
 
 
 
 
 
 


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