Hi, Yes, this is deliberate. The 3-site models are already almost impossible to optimise as they have so many minima, and this is an active research area in the dispersion field. Introducing R20A != R20B != R20C increases the number of minima exponentially, making the problem totally impossible to solve. So that is why we have R20A = R20B = R20C in the model. It might be possible to create 'full' versions of these models where these rates are different, but I think the field needs to develop further before this is of any use.
But the infrastructure in lib.dispersion does support R20A != R20B != R20C. The reason for this is that the lib.dispersion modules can be directly used to investigate the optimisation space problems. I would like to have this as a powerful tool for investigating this multi-site, multi-rate problem in the future. Regards, Edward On 24 June 2014 11:14, Troels Emtekær Linnet <[email protected]> wrote: > Hi Ed. > > As far as I can see, R20B, and R20C is not used in ns_mmq_2site and 3site? > > def func_ns_mmq_2site(self, params): > """Target function for the combined SQ, ZQ, DQ and MQ CPMG numeric > solution. > > @param params: The vector of parameter values. > @type params: numpy rank-1 float array > @return: The chi-squared value. > @rtype: float > """ > > # Scaling. > if self.scaling_flag: > params = dot(params, self.scaling_matrix) > > # Unpack the parameter values. > R20 = params[:self.end_index[0]] > dw = params[self.end_index[0]:self.end_index[1]] > dwH = params[self.end_index[1]:self.end_index[2]] > pA = params[self.end_index[2]] > kex = params[self.end_index[2]+1] > > But they are parsed to the lib function. > > # Back calculate the R2eff values for each experiment type. > self.r2eff_ns_mmq[ei](M0=self.M0, R20A=r20, R20B=r20, pA=pA, > dw=aliased_dw, dwH=aliased_dwH, kex=kex, > inv_tcpmg=self.inv_relax_times[ei], tcp=self.tau_cpmg[ei], > back_calc=self.back_calc[ei], num_points=self.num_disp_points[ei], > power=self.power[ei]) > > Is this by purpose? > _______________________________________________ > relax (http://www.nmr-relax.com) > > This is the relax-devel 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-devel _______________________________________________ relax (http://www.nmr-relax.com) This is the relax-devel 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-devel
