On Thu, May 13, 2010 at 09:34:14AM +0100, Gary wrote: > Hi all, > > First, thank you for your efforts in providing the octave packages. > This would not be possible without you! > > PROBLEM: > I'm quite new to octave but have managed to cobble a script together > that uses leasqr with bounded parameters to fit model parameters to > experimental values. The code has been working well, but with certain > initial parameters the bounds I've set are not respected and the value > of some parameters, almost always only one, become -ve (they should > all be +ve). I've searched the archive and the web for reports of > similar problems but couldn't find anything relevant. > > VERSION DETAILS: > octave: 3.2.3 > optim: 1.0.12 > os: kubuntu 10.04 > > RELEVANT CODE: > ## generate parameters for leasqr > pin_ones = ones(length(pin),1); > > stol=0.0001; # scalar tolerance on fractional improvement in scalar > sum ofsquares = sum((wt.*(y-f))^2); default stol = .0001; > niter=40; # maximum number of iterations; default = 20; > wt = 1 ./ (0.05*expt_data .* ones(length(expt_data),1)).^(2); # > statistical weighting = 1/(variance)^2 > dp = 0.001*pin_ones; # fractional increment of p for numerical > partial derivatives default = .001*ones(size(pin)); > dFdp = 'dfdp'; # name of partial derivative function in > quotes; > default is 'dfdp' > max_Dnt = 1e40; > options.bounds = [ 1e-30*pin_ones, max_Dnt*pin_ones ]; # > constraints > (also applied to optimised input file parameters) > > ## Call ctave fitting routine > [f,p,kvg,iter,corp,covp,covr,stdresid,Z,r2] = leasqr(expt_Vg_all, > expt_data, pin, 'F', stol, niter, wt, dp, dFdp, options);
Please submit a self-contained script, as short and clear as possible, to reproduce the bug. Olaf ------------------------------------------------------------------------------ _______________________________________________ Octave-dev mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/octave-dev
