When param.fixed_to is not None, the parameter will be held fixed at the specified value during a fit. However, if the user does not remember that the parameter is being held fixed and sets param.user_estimate to some value with the expectation that it will be used for parameter estimation, the value provided by user is ignored without any warning. This is not a huge problem, but I think it would be helpful if a warning (or other log message) was emitted during the fit in this case, to let the user know that their estimate won't do anything.
When
param.fixed_tois notNone, the parameter will be held fixed at the specified value during a fit. However, if the user does not remember that the parameter is being held fixed and setsparam.user_estimateto some value with the expectation that it will be used for parameter estimation, the value provided by user is ignored without any warning. This is not a huge problem, but I think it would be helpful if a warning (or other log message) was emitted during the fit in this case, to let the user know that their estimate won't do anything.