casa6

import os

from taskinit import *

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def makemask(cleanbox=None,vis=None,imagename=None,mode=None,nchan=None,start=None,width=None,step=None,imsize=None,cell=None,phasecenter=None,stokes=None,field=None,spw=None):

    """Derive a mask image from a cleanbox blc, trc regions 

​

    Keyword arguments:

        cleanbox -- Cleaning region:

                default: [] defaults to inner quarter of image

                Two specification types:

                Explicit pixel ranges

                   example: cleanbox=[[110,110,150,145],[180,70,190,80]]

                   cleans two regions defined by the pixel ranges

                Filename with pixel values with ascii format:

                   <fieldid blc-x blc-y trc-x trc-y> on each line

    ----------------------------------------------------------------

        vis -- Name of input visibility file (MS)

                default: none; example: vis='ngc5921.ms'

        imagename -- Name of output mask image

                default: none; example: imagename='ngc5921.mask'

        mode -- Type of selection 

                default: 'mfs'; example: mode='channel'; 

                Options: 'mfs', channel'

        nchan -- Number of channels to select

                default: -1 (all); example: nchan=45

        start -- Start channel

                default=0; example: start=5

        width -- Channel width (value > 1 indicates channel averaging)

                default=1; example: width=5

        step -- Step in channel number

                default=1; example: step=2      

        imsize -- Image size in spatial pixels (x,y)

                default = [256,256]; example: imsize=[512,512]

        cell -- Cell size in arcseconds (x,y)

                default=[0,0] = none; example: cell=[0.5,0.5]

        phasecenter -- direction measure  or fieldid for the mosaic center

                default: '' (imply field=0 as center); example: phasecenter=6

                or phasecenter='J2000 19h30m00 -40d00m00'

        stokes -- Stokes parameters to image

                default='I'; example: stokes='IQUV'; 

                Options: 'I','IV','IQU','IQUV'

       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 a field index

                 otherwise, it is assumed 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 adn 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, 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

​

    """

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