Hi, That is roughly correct. Just set the lower and upper bound to 0.111 and set the number of increments for that parameter to 1. Then it is like a grid search without S2f being present, or being fixed to 0.111.
Regards, Edward On 6 April 2011 18:38, Tiago Pais <[email protected]> wrote: > Hi Ed, > Thanks for the quick reply. > Let's see if I understand your suggestion. For example, the mf_multimodel.py > sample script performs a grid search minimization using the grid_search > function. So if I insert an array of upper and lower bounds for the > parameters in the model I can constrain the interval of possible results, > correct? If so, what is the sequence for the parameters in the array? > TP > > > > -----Original Message----- > From: Edward d'Auvergne [mailto:[email protected]] > Sent: quarta-feira, 6 de Abril de 2011 17:13 > To: Tiago Pais > Cc: [email protected] > Subject: Re: How to set S2f to 0.111? > > Hi, > > Unfortunately, there is no ability to fix one of the model-free > parameters during optimisation in relax yet. This is something that > has been requested one or two times over the years. This is > complicated as the gradients and Hessians (first and second partial > derivates) need to be modified with this in mind, as the curvature of > the space changes. The fixed parameter is not part of the gradient or > Hessian, and has to be removed. This really complicates the target > function, gradient, and Hessian and, due to the low demand, has not > been implemented. > > Are you able to optimise this parameter and see if you get 0.111? And > are you able to extract the timescale of this process (the methyl > group rotamer jumps)? From memory, someone has optimsed these models > using a grid search. This coarse optimisation can be performed in > relax as you are able to specify the fine details of the grid search. > It is slower, but will do the job. You could even implement a zooming > grid search if your scripting skills are up to it to be able to > relatively quickly find the parameters to high precision. Anyway, I > hope this info helps. > > Regards, > > Edward > > > > > > On 6 April 2011 17:39, Tiago Pais <[email protected]> wrote: >> Hi, >> >> I would like to make an analysis of side-chain relaxation data with the > S2f >> parameter (in model 5) set to 0.111. >> >> Is it possible to do this with RELAX? How? >> >> Thanks in advance. >> >> Cheers >> >> Tiago P >> >> >> >> ************************************** >> >> Tiago Pais, PhD. student >> >> Cell Physiology & NMR >> >> Instituto de Tecnologia Química e Biológica-Oeiras >> >> >> >> __________ Information from ESET NOD32 Antivirus, version of virus > signature >> database 6019 (20110406) __________ >> >> The message was checked by ESET NOD32 Antivirus. >> >> http://www.eset.com >> >> _______________________________________________ >> relax (http://nmr-relax.com) >> >> This is the relax-users mailing list >> [email protected] >> >> To unsubscribe from this list, get a password >> reminder, or change your subscription options, >> visit the list information page at >> https://mail.gna.org/listinfo/relax-users >> >> > > __________ Information from ESET NOD32 Antivirus, version of virus signature > database 6019 (20110406) __________ > > The message was checked by ESET NOD32 Antivirus. > > http://www.eset.com > > > > > __________ Information from ESET NOD32 Antivirus, version of virus signature > database 6019 (20110406) __________ > > The message was checked by ESET NOD32 Antivirus. > > http://www.eset.com > > > _______________________________________________ relax (http://nmr-relax.com) This is the relax-users mailing list [email protected] To unsubscribe from this list, get a password reminder, or change your subscription options, visit the list information page at https://mail.gna.org/listinfo/relax-users
