Dear all,
I have the following problem:
In some fits using Artemis (Demeter 0.9.25) I will get negative values
for parameters where it makes no sense at all.
For example, when trying to fit two first shell paths, Pt-Pt and Pt-O,
for a Pt nanoparticle,
sigma^2 for the Pt-O path becomes negative.
Obviously, sigma^2 has to be a positive number.
My questions:
1. Why does the fit algorithm do this?
2. What can I do to avoid this?
I know that there are most likely significant problems with my fit if
this behaviour occurs.
As far as I know it's possible to impose restrictions in Artemis and if
anyone could point me
towards a tutorial explaining how to implement restrictions that might
be a first step in the right direction.
Currently, the chapter "Constraints and restraints" in the Artemis
documentation is "Coming soon......".
With kind regards,
Felix
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