Main Page | Modules | Data Structures | File List | Data Fields | Globals | Related Pages

create_mask

Creates the extraction mask according to the optical model

Parameters:
-mask mask Input mask (from find_mpup)
-max max Intput max (from find_max)
-cal arc Calibration frame
-reftable arc_ref Calibration lambda reference table
-fit 1,1 Arc and Continuum fitting flag.
  • If FITCONT=n, fit every n-th max line only (i.e. every line for n=1).
  • If FITXXX<=0, the corresponding fit is actually not performed
-tol 1.e-2 Fitting tolerance
-default Read default configuration (and save it to mask)
-blaze Use blaze function in fitting process (not implemented yet)
-nolocal Do not compute local adjustment to mask
Returns:
Error status

Todo:
To compute the sky coordinates of the lenses, one needs to come back to the MLA level, study the distortion there, undistort the observed positions, and then compute the sky coordinates.

Implement the blaze option, in order to fit 0th/2nd orders weighted according to the blaze function.

Discard the need for the arc frame or for the max if they are not actually adjusted.

It is probably not a good idea to use a classical minimization scheme on such a noisy ill-conditionned problem. Maybe have a look at ``simulated annealing'' algorithm (cf. GSL), which could be however computation-time costly.

Compute decent value for arc normalisation factor glnormmax (arc frame mean? 1st step value?)

Use Fit_polynom (with automatic adjustment of polynomial degree) instead of fit_poly_rej_nag_tab in local adjustment. Furthermore, since the sigma=f(lambda) is noisy, the sigma-clipping is not rebost enough, and one should enforce a physical selection over sigma right after pup_get_maxdata

Note:
You don't really need the arc frame if you don't fit it. The program still need a frame (to be changed), but as it is actually not used, the continuum exposure can do the trick.

Warning:
There's no way to check the channel of the input max.

Generated on Thu Oct 27 00:00:24 2005 for Snifs by doxygen 1.3.5