Hi Frank, Thank you for your detailed explanations. Really, I think so, this little workaround is useful to some topas users. Cheers Habib -------Message original------- De : Frank Girgsdies Date : 12/03/2010 10:15:22 A : Habib Boughzala; Rietveld_l@ill.fr Sujet : Re: Réf. : RE: Topas prm keyword In the GUI mode, you simply initialize a parameter by entering its name in into the grid on the "codes" tab, without the "=" sign! This is equivalent to changing the line of code you've sent from Site OH num_posns 4 x 0 y 0 z 0.315309 occ O =oh; : 0.5 min =0; max =0.5 beq 1 to Site OH num_posns 4 x 0 y 0 z 0.315309 occ O oh; : 0.5 min =0; max =0.5; beq 1 i.e. delete the "=" sign before the "oh". Thus, I think there is no need to use the "prm" command (or the launch mode) in your case. However, there may be cases where it could be convenient to declare a parameter separately. For example, I have a solid solution series where all lattice parameters are a known function of the stoichiometry parameter "X". If I now want to do some restrictive fitting (instead of four independent monoclinic lattice parameters I would like to refine just "X"), then I can use the following workaround to emulate something like the "prm" command in the GUI: I simply add an additional dummy site to my structure phase. Dummy site means that I may chose the name of the site and the element freely, but set the occupancy to zero. Now, I can use the x, y and z coordinates and the Beq as "containers" for my parameters, because with zero occupancy, the dummy atom will not contribute to the calculated intensities! I enter the starting values for my parameter(s) in the "Values" tab of the grid and the parameter name(s) in the "Codes" tab. If a parameter is not to be refined, a "!" needs to precede the parameter name. Maybe this little workaround is useful to some of you. I should add that this trick works in Topas version 3, I'm not sure if it does with other versions... Best wishes, Frank Habib Boughzala wrote: > So, > > How to initialize a variable ? > > Cheers > > /-------Message original-------/ > > /*De :*/ Kern, Arnt <mailto:arnt.k...@bruker-axs.de> > /*Date :*/ 12/03/2010 09:05:03 > /*A :*/ 'ian.mad...@csiro.au' <mailto:ian.mad...@csiro.au>; > habib.boughz...@ipein.rnu.tn <mailto:habib.boughz...@ipein.rnu.tn>; > rietveld_l@ill.fr <mailto:rietveld_l@ill.fr> > /*Sujet :*/ RE: Topas prm keyword > > The keyword "prm" is exclusive to so-called Launch Mode operation, > please see also the Technical Reference manual. > > Cheers, > > Arnt > > ------------------------------------------------------------------------ > *From:* ian.mad...@csiro.au [mailto:ian.mad...@csiro.au] > *Sent:* Freitag, 12. März 2010 08:53 > *To:* habib.boughz...@ipein.rnu.tn; rietveld_l@ill.fr > *Subject:* RE: Topas prm keyword > > Try prm not Prm (ie with all lower case letters) > > > > /Cheers/ > / / > /o----------------------------oo0oo----------------------------o/ > / Ian Madsen/ > / Team Leader - Diffraction Science/ > / CSIRO Process Science and Engineering/ > / Box 312, Clayton South 3169/ > / Victoria, AUSTRALIA/ > / Phone +61 3 9545 8785 direct/ > / +61 3 9545 8500 switch/ > / +61 (0) 417 554 935 mobile/ > / FAX +61 3 9562 8919/ > / Email //_____ian.mad...@csiro.au_/ <mailto:ian.mad...@csiro.au>/ / > /o----------------------------oo0oo----------------------------o/ > > > > ------------------------------------------------------------------------ > *From:* Habib Boughzala [mailto:habib.boughz...@ipein.rnu.tn] > *Sent:* Friday, 12 March 2010 6:45 PM > *To:* rietveld_l@ill.fr > *Subject:* Topas prm keyword > > Hi, > > My mail is intended to Topas users, especially to Dr. Alan Coelho > > I am trying to determine the carbonate / hydroxide ratio in some compounds
> This is a part of 'str' block In the input file (*.inp) > __________________________________________________________________________ > Str > .... > Prm oh 0.5 > .... > Site OH num_posns 4 x 0 y 0 z 0.315309 occ O =oh; : 0.5 min =0; > max =0.5; beq 1 > Site C num_posns 2 x 0 y 0 z 0 occ C =1 - 0.5 oh; : 1 min =0; max > =0.5; beq 1 > Site Oc num_posns 12 x 0.040114 y 0.953411 z 0.629971 occ O =(1 - > 0.5 oh) / 3; : 1 min =0; max =0.25; beq 1 > __________________________________________________________________________ > > Topas 4.2 run failed... Error: prm command in unrecognised !!! > > Any suggestion ? > > P.S. This keyword is unrecognised too in all tutorials inp file examples !!! > > Thanks for help > > Habib > > Prof. Habib Boughzala. > *L*aboratoire de *M*atériaux et *C*ristallochimie. > *A*ssociation *T*unisienne de *C*ristallographie > I.P.E.I.N. Mrezga, 8000. > Nabeul. Tunisie. > > > > > ----------------------------------------------------------------------------- ------ > > > > Bruker AXS GmbH, Karlsruhe > > HRB 107524 Amtsgericht Mannheim, Umsatzsteuer-Ident.Nr. DE812037551, > Geschäftsführer - Dr. Frank Burgäzy, Bernard Kolodziej, Stephan Franz > Westermann > > > > ----------------------------------------------------------------------------- ------ > > > > Der Inhalt dieser E-Mail ist vertraulich und ausschliesslich fuer den > bezeichneten Adressaten bestimmt. Wenn Sie nicht der vorgesehene > Adressat dieser E-Mail oder dessen Vertreter sein sollten, so beachten > Sie bitte, dass jede Form der Kenntnisnahme, Veroeffentlichung, > Vervielfaeltigung oder Weitergabe des Inhalts dieser E-Mail unzulaessig > ist. Wir bitten Sie, sich in diesem Fall mit dem Absender der E-Mail in > Verbindung zu setzen. > > > > The information contained in this email is confidential. It is intended > solely for the addressee. Access to this email by anyone else is > unauthorized. If you are not the intended recipient, any form of > disclosure, reproduction, distribution or any action taken or refrained > from in reliance on it, is prohibited and may be unlawful. Please notify > the sender immediately. > > > > ----------------------------------------------------------------------------- ------ > > > > > > > <http://www.incredimail.com/app/?tag=default_stamp&id=512&lang=12&rui=105259115>