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Version 1.9 Build 1556

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simulator.setfield - Function

	Package	synthesis
	Module	simulator
	Tool	simulator

Set one or more observed fields

Synopsis
setfield(row, sourcename, sourcedirection, integrations, xmospointings, ymospointings, mosspacing, distance)

Description
Set one or more observed fields, including name, coordinates, number of pointings for a mosaic observation, etc. Can be invoked multiple times for a complex observation. Must be invoked at least once before create.

If the distance to the object is set then the phase term includes a curvature for the near-field effect at the center of the image.

Arguments

row		Row number in the field table
		Allowed:	Int
		Default:	1
sourcename		Name of source or field (must be specified)
		Allowed:	String
		Default:	'unknown'
sourcedirection		Coordinates of source to be observed
		Allowed:	MDirection
integrations		Number of integrations before changing source
		Allowed:	Int
		Default:	1
xmospointings		Number of mosaic pointings in the horizontal direction
		Allowed:	Int
		Default:	1
ymospointings		Number of mosaic pointings in the vertical direction
		Allowed:	Int
		Default:	1
mosspacing		Spacing between mosaic pointings, in units of lambda/2D
		Allowed:	Float
		Default:	0
distance		Distance to the object
		Allowed:	String
		Default:	'0km'

Example

  mysim.settimes( integrationtime='10s', gaptime='0s', usehourangle=T,
                starttime='0s', stoptime='3600s', 
                referencetime=reftime);
  mysim.setconfig(telescopename='VLA', x=xx, y=yy, z=zz, dishdiameter=diam, 
                mount='alt-az', antname='VLA',
                coordsystem='local', referencelocation=dm.observatory('vla'));

  mysim.setspwindow(row=1, spwname='XBAND', freq='8GHz', deltafreq='50MHz',
                   freqresolution='50MHz', nchannels=1, stokes='RR
                   LL');
  dir0 := dm.direction('B1950',  '16h00m0.0', '50d0m0.000')
  mysim.setfield( row=1, sourcename='SIMU1', sourcedirection=dir0,
                integrations=1, xmospointings=1, ymospointings=1,
                mosspacing=1.0);

  mysim.create(newms='something.ms')

In the above example we simulate a single pointing measurement set. Where as in the case below we change the setfield to simulate a mosaic observation with 6 pointings spaced by 1/2 primary beams.

 
 mysim.setfield( row=1, sourcename='SIMU1', sourcedirection=dir0,
                integrations=1, xmospointings=3, ymospointings=2,
                mosspacing=1.0);

  mysim.create(newms='something.ms')

And if we wanted to have 2 distinct pointings we would proceed as below

  dir0 := dm.direction('B1950',  '16h00m0.0', '50d0m0.000')
  mysim.setfield( row=1, sourcename='SIMU1', sourcedirection=dir0,
                integrations=1, xmospointings=1, ymospointings=1,
                mosspacing=1.0);
  dir1 := dm.direction('B1950',  '16h20m0.0', '52d0m0.000')
  mysim.setfield( row=2, sourcename='SIMU2', sourcedirection=dir0,
                integrations=1, xmospointings=1, ymospointings=1,
                mosspacing=1.0);
  mysim.create(newms='something.ms')