parameter constraints with genfit?

[ptc-2930462]

Is it possible to include parameter constraints when using genfit? If so, how is it implemented?

I need to fit a non-linear equation (Richards function) and genfit crashes with the current setting. I supply all the derivative functions with respect to the parameters.

Any insight is greatly appreciated.

Ulrich Hopfer

[MikeArmstrong]

I would suggest posting a worksheet.

[ptc-2930462]

I have added the worksheet to my question on constrains with genfit, as suggested by Mike.

Ulrich

[MikeArmstrong]

You forgot to upload the data

[Werner_E]

Yet another thread which is more than one hour old and did show up for me 15 minutes ago. Looks like its getting worse.

[MikeArmstrong]

It seems to be worse tonight. Maybe PTC are playing tricks on us :-).

[ptc-2930462 · Accepted solution]

Genfit only uses the derivatives with respect to the fitted parameters. I looked up the algorithm for the Levenberg-Marquardt method for non-linearized fitting.