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calibrater.modelfit - Function

2.2.1 Model fitting


Description

This method fits single-component models (points, elliptical Gaussians or elliptical Disks_ to the CORRECTED_DATA of the selected field. A first guess for the component parameters may be specified in the par parameter.

Arguments





Inputs

vary

If specified where T, let this parameter (in par) vary in fit

allowed:

boolArray

Default:

niter

Number of non-linear fitting iterations

allowed:

int

Default:

0

compshape

Component shape, P=point G=gaussian

allowed:

string

Default:

P

par

Initial guess for fit parameters (default is for ”P)”I flux, rel RA, rel Dec, 1,0, 0.0, 0.0 are defaults

allowed:

doubleArray

Default:

1.0 0.0 0.0

file

If specified, output componentslist file name, if empty don’t write componentslist file

allowed:

string

Default:

Returns
doubleArray

Example

 
 
cb.open(’ngc5921.ms’);  
cb.selectvis(field=’1331*’)  
cb.modelfit(compshape=’P’,par=[15.0,0.0,0.0])  
cb.close();  
 
 
This example fits a point source mode using 15.0 Jy at the origin (phase center)  
as a first guess.  
 
 
 
cb.open(’ngc5921.ms’);  
cb.selectvis(field=’1331*’)  
cb.modelfit(compshape=’G’,par=[15.0,0.0,0.0,2.0,1.0,0.0])  
cb.close();  
 
 
This example fits a Guassian model with a starting  
guess of 15 Jy at the phase center (0,0), with 2.0 arcsec major axis,  
1.0 axial ratio, at position angle 0.0 deg.  
 

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