FORWARD FITTING ALGORITHM

The Forward-Fitting method is based on the assumption that the spatial map can be well represented by a small number of elemental  source structures, each of which can be characterized by just a few parameters.  Such structures might be circular, elliptical, or curved elliptical Gaussians (a loop).  Such Gaussians sources can be represented by 4,6, or 7 parameters respectively.

In the Forward-Fitting algorithm, 'pixelized' maps of multiple Gaussian components are created and used to calculate a model modulation profile which is then compared to the observed modulation profile.  The map iteratively evolves into a best-fit image which yields well-quantified parameters. 

The Forward fit algorithm uses the ANNSEC coordinate system internally.

 

Using the Forward Fit algorithm at the command line:

Select algorithm 

o->set, image_algorithm='forward'

or 'for' or 'hsi_forwardfit'

Object Class 

HSI_FORWARDFIT


Extract Object

ff_obj = o->get(/obj,class='hsi_forwardfit') 

Extract the object used in the hsi_image object, o

Parameter Prefix 

ff, e.g.
ff_n_gaussians = o->get(/ff_n_gaussians)
ff_control = o->get(/ff, /control)
ff_info = o-> get(/ff, /info)
ff_all = o->get(/ff)

All parameter names specific to this algorithm have this prefix

Parameter Table 

Forward Fit Object Parameter Table

List and short description of control and info parameters specific to this algorithm

 


THEORY


SOFTWARE TUTORIALS


TEST IMAGES