[Ifeffit] Fwd: problems with setting parameters in new Artemis (Demeter 0.9.16)

Cristina Alonso Escobar criales at itq.upv.es
Fri Feb 28 06:52:32 CST 2014


Dear All,

I am trying to fit the first FT shell in Artemis with a mixture of two  
different compounds (octahedral and tetrahedral models). I would like  
to quantify the ratio between this two compounds in my sample so I  
decided to multiply So2 by a parameter called "a" in one model and by  
"(1-a)" in the other.

I would like to know:

1.- How can I restrain "a" ? I tried to  manually add a restraint, but  
I do not know how to make an interval restraint...( 0<a<1)

2.- If you select "restrain" and after in the math expression "build  
restrain from ..."
What is the meaning of scale by?
Why the program duplicate the restrain (i.e restrain- a and restrain-  
res_a - 1* penalty (a, 0, 1)?
I think I am not doing well because the value of my parameter "a" is  
suspiciously always 0.



Thank you in advance,



*** *** *** *** *** *** *** *** ***

Cristina Alonso-Escobar. PhD student

Instituto de Tecnología Química (UPV-CSIC)
Avda. de los Naranjos s/n
46022 Valencia (Spain)

http://itq.upv-csic.es

Tfno: +34 96 387 7800
Fax:  +34 96 387 9444

----- Terminar mensaje reenviado -----


*** *** *** *** *** *** *** *** ***

Cristina Alonso-Escobar. PhD student

Instituto de Tecnología Química (UPV-CSIC)
Avda. de los Naranjos s/n
46022 Valencia (Spain)

http://itq.upv-csic.es

Tfno: +34 96 387 7800
Fax:  +34 96 387 9444




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