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imagerpositiontest.set_sim_parms - Function

	Package	synthesis
	Module	synthesistester
	Tool	imagerpositiontest

Set up the parameters to be used when creating the default simulator.

Synopsis
set_sim_parms(frequency, docorrupt, scalefactor, nchan, nsources, noiselevel, nfields, deltafreq, freqresolution, sourcedirection, source_spread, minflux, maxflux, minsep, seed)

Description
Set up the parameters to be used when creating the default simulator. These parameters are used at various stages of the processing by dotests.

Arguments

frequency		The observing frequency
		Allowed:	Quantity (frequency)
		Default:	'22GHz'
docorrupt		Add noise to the simulated data by calling simulator.corrupt()?
		Allowed:	Boolean
		Default:	F
scalefactor		The array scale factor. Controls the size of the baselines (and hence the resolution in the images)
		Allowed:	Float > 0
		Default:	1.0
nchan		Number of channels in the simulated dataset
		Allowed:	Integer > 0
		Default:	1
nsources		Number of sources to simulate
		Allowed:	Integer > 0
		Default:	4
noiselevel		The level of the noise to add when docorrupt==T
		Allowed:	Quantity (flux density)
		Default:	'1Jy'
nfields		The number of fields to simulate
		Allowed:	Integer > 0 and non prime if > 2
		Default:	1
deltafreq		Channel seperation
		Allowed:	Quantity (frequency)
		Default:	'1MHz'
freqresolution		Frequency resolution
		Allowed:	Quantity (frequency)
		Default:	'1MHz'
sourcedirection		Direction of source
		Allowed:	MDirection
		Default:	dm.direction('J2000', '16h00m0.0', '50d0m0.000')
source_spread		Determines over how large of field the sources will be dispersed, in multiples of the field of view
		Allowed:	Float > 0
		Default:	1.0
minflux		The minimum flux density for a source. Flux densities are determined using a uniform distribution between minflux and maxflux
		Allowed:	0 < Float <= maxflux
		Default:	3.0
maxflux		The maximum flux density for a source. Flux densities are determined using a uniform distribution between minflux and maxflux
		Allowed:	Float >= minflux
		Default:	3.0
minsep		The minimum source separation allowed in arcsec. No two sources will be closer than this. Note that if minsep is chosen to be too large for the field of view, source_spread, and nsources, a valid source position distribution will not be possible. In this case, make_default_cl() (or dotests()) will fail (with an informative message)
		Allowed:	Float >= 0
		Default:	5
seed		The value to use for the simulator random number generator seed
		Allowed:	Float
		Default:	185349251

Returns
T or fail

Example

- include 'imagerpositiontest.g';
- ipt := imagerpositiontest();
# set up a single field mem and corrupt the data
# set the number of sources, flux density range, and minimum
# separation as well.
- ipt.set_sim_parms(scalefactor=2,docorrupt=1,seed=426,noiselevel='0.5Jy',
+ nsources=10, minflux=20,maxflux=30,minsep=10);
- ipt.set_deconvolution_function('mem');
- ipt.set_mem_parms(algorithm='entropy',niter=25,sigma='0.1Jy');
- ipt.dotests();