URL: <http://gna.org/bugs/?22409> Summary: Minimisation of R1rho model give random results Project: relax Submitted by: tlinnet Submitted on: Wed 30 Jul 2014 09:21:29 PM UTC Category: relax's source code Specific analysis category: Relaxation dispersion Priority: 5 - Normal Severity: 4 - Important Status: None Assigned to: bugman Originator Name: Originator Email: Open/Closed: Open Release: Repository: trunk Discussion Lock: Any Operating System: All systems _______________________________________________________ Details: This was discussed in: http://thread.gmane.org/gmane.science.nmr.relax.devel/6538 Systemtest Relax_disp.test_r1rho_kjaergaard_auto_check_graphs shows that the error value constantly are changing between each run of analysis. This is properly because the number of Monte-Carlo simulation is only set to 3. This can sometimes happens if the base data are exponential curves, as then the R2eff errors are determined by Monte Carlo simulations which are random. And because it is a test the number of simulations are low so the randomness is quite large. This randomness will then be propagated into the higher models. Apart from the unique case of Monte Carlo simulations (or the unit tests for a few other functions which use the 'random' Python module), a test should return the same result to machine precision every single time. It must be identical. _______________________________________________________ Reply to this item at: <http://gna.org/bugs/?22409> _______________________________________________ Message sent via/by Gna! http://gna.org/