Re: voigt backward compatibility

Hi,

 > This is because the voigt() model has changed, apparently.
> This is a backward compatibility problem.  Is the old voigt model still around?
 > Also, when did voigt() change?
Consider the file Changes.txt from the ISIS sources:
#  Changes since 1.4.5 (released Mar 2007)
#  9.  Voigt profile norm now includes factor 1/(sqrt(PI)*Doppler_width)
#     (set Isis_Voigt_Is_Normalized=0 to restore the previous behavior

 > What are the formulae to convert between old and new voigt parameters?
Before, ISIS's voigt() implemented the Voigt-function H(a,v) rather than 
the normalized (\int \Phi(\nu) d\nu = 1) Voigt-profile
   Phi(\nu) = \frac{1}{sqrt{\pi}\Delta\nu_D} \times
         H(\frac{\nu-\nu_0}{\Delta\nu_D}, \frac{\Gamma}{4\pi\Delta\nu_D})
The parameter voigt().norm was thus somehow normalized to the 
Doppler-broadening \Delta\nu_D = (thermal velocity)/c \times \nu_0
and thus dependent on the position \nu_0 of the line.

> Also, is there a way to tell what version of ISIS I'm running at run-time
This is contained in the variable _isis_version .

Cheers,

Manfred


-- 
Manfred Hanke  Manfred.Hanke(at)sternwarte.uni-erlangen.de
Dr. Karl Remeis-Sternwarte,  Universität Erlangen-Nürnberg
Sternwartstraße 7,    96049 Bamberg
Tel. (0951) 95222-34                   Fax (0951) 95222-22
www: http://pulsar.sternwarte.uni-erlangen.de/hanke
--

----
You received this message because you are
subscribed to the isis-users list.
To unsubscribe, send a message to
isis-users-request_at_email.domain.hiddenwith the first line of the message as:
unsubscribe