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0.1.16 csvclean

Requires:

Synopsis
This task does an invert of the visibilities and deconvolve in the image plane.

Description

This task does an invert of the visibilities and deconvolve in the image plane. It does not do a uvdata subtraction (aka Cotton-Schwab major cycle) of model visibility as in clean. - For ALMA Commissioning

Arguments





Inputs

vis

Name of input visibility file

allowed:

string

Default:

imagename

Name of image

allowed:

string

Default:

field

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

allowed:

string

Default:

spw

Select spectral window/channels

allowed:

any

Default:

variant

advise

Boolean to determine if advice on image cell is requested

allowed:

bool

Default:

False

mode

define the mode to operate csvclean: option continuum, cube

allowed:

string

Default:

continuum

nchan

Number of channels (planes) in output image; -1 = all

allowed:

int

Default:

-1

width

width of output spectral channels

allowed:

variant

Default:

variant 1

imsize

Image size in pixels (nx,ny), symmetric for single value

allowed:

intArray

Default:

256256

cell

arcsec

The image cell size in arcseconds [x,y].

allowed:

doubleArrayarcsec

Default:

1.01.0

phasecenter

Image center: direction or field index

allowed:

any

Default:

variant

niter

Maximum number of iterations

allowed:

int

Default:

500

weighting

Type of weighting

allowed:

string

Default:

natural

restoringbeam

Output Gaussian restoring beam for CLEAN image

allowed:

stringArray

Default:

interactive

Create a mask interactively or not.

allowed:

bool

Default:

False

Example

 
 
        This task does not do a uvdata subtraction (aka Cotton-Schwab major cycle)  
        of model visibility as in clean. - For ALMA Commissioning  
 
Keyword arguments:  
vis -- Name of input visibility file  
         default: none; example: vis=’ngc5921.ms’  
 
imagename -- Name of output CASA image. (only the prefix)  
                   default: none; example: imagename=’m2’  
                   output images are:  
                 m2.image; cleaned and restored image  
                        With or without primary beam correction  
                 m2dirty.image; dirty image  
                 m2psf.image; point-spread function (dirty beam)  
                 m2.model; image of clean components  
                 m2.mask; image containing clean regions, when interative=True  
 
field -- Select fields in mosaic.  Use field id(s) or field name(s).  
                  [’go 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’; field named 3C286 and 3C295  
              field = ’3,4C*’; field id 3, all names starting with 4C  
 
spw -- Select spectral window/channels  
           NOTE: This selects the data passed as the INPUT to mode  
           default: ’’= all spectral windows and channels  
                spw=’0~2,4’; spectral windows 0,1,2,4 (all channels)  
                spw=’0:5~61’; spw 0, channels 5 to 61  
                spw=’<2’;   spectral windows less than 2 (i.e. 0,1)  
                spw=’0,10,3:3~45’; spw 0,10 all channels, spw 3,  
   channels 3 to 45.  
                spw=’0~2:2~6’; spw 0,1,2 with channels 2 through 6 in each.  
                spw=’0:0~10;15~60’; spectral window 0 with channels  
    0-10,15-60  
                spw=’0:0~10,1:20~30,2:1;2;3’; spw 0, channels 0-10,  
                      spw 1, channels 20-30, and spw 2, channels, 1,2 and 3  
        advise -- This determines whether advice for imsize and cell is  
                  requested. If set to True. It won’t run clean but return  
                  values for imszise and cell estimated for the longest  
                  baseline in the data  
 
imsize -- Image pixel size (x,y).  DOES NOT HAVE TO BE A POWER OF 2  
               default = [256,256]; example: imsize=[350,350]  
               imsize = 500 is equivalent to [500,500].  
               Avoid odd-numbered imsize.  
 
cell -- Cell size (x,y)  
               default= ’1.0arcsec’;  
               example: cell=[’0.5arcsec,’0.5arcsec’] or  
               cell=[’1arcmin’, ’1arcmin’]  
               cell = ’1arcsec’ is equivalent to [’1arcsec’,’1arcsec’]  
               NOTE:cell = 2.0 => [’2arcsec’, ’2arcsec’]  
 
       phasecenter -- direction measure  or fieldid for the mosaic center  
                default: ’’ => first field selected ; example: phasecenter=6  
                or phasecenter=’J2000 19h30m00 -40d00m00’  
 
mode -- this determines what kind of image to make  
                continuum or cube. In continuum all the selected data  
                channels are combined in a 1 channel image using  
                multifrequency synthesis.  
                options are ’cube’ and ’continuum’  
                default: ’continuum’  
  >>> mode=’cube’ expandable parameters  
               nchan -- sets the number of channel in the output  
               image. e.g nchan=10  
 
               width -- image channel width in terms of the number of  
                        channel of the first spw of the data selected  
                        e.g width=2  
 
 
 
niter -- Maximum number of iterations,  
               if niter=0, then no CLEANing is done ("invert" only)  
               default: 500; example: niter=5000  
 
weighting -- Weighting to apply to visibilities:  
               default=’natural’; example: weighting=’uniform’;  
               Options: ’natural’,’uniform’,’briggs’,  
                       ’superuniform’,’briggsabs’,’radial’  
 
restoringbeam -- Output Gaussian restoring beam for CLEAN image  
               [bmaj, bmin, bpa] elliptical Gaussian restoring beam.  
               Default units are in arc-seconds for bmaj and bmin, and in degrees  
               for bpa. Default: restoringbeam=[]; Use PSF calculated  
               from dirty beam.  
               example: restoringbeam=[’10arcsec’] or restorinbeam=’10arcsec’, circular Gaussian.  
                        FWHM 10 arcseconds example:  
                        restoringbeam=[’10.0’,’5.0’,’45.0deg’] 10"x5"  
                        at 45 degrees  
 
interactive -- Create a mask interactively or not.  
         default=False; example: interactive=True  
         The viewer will open with the image displayed. Select the  
         region for the mask and double click in the middle of it.  
 


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