[Ifeffit] max number of restraints

Bruce Ravel bravel at anl.gov
Fri Apr 13 14:50:29 CDT 2007

On Friday 13 April 2007 14:29, Matt Newville wrote:
> Hi Victor,
> It should be
>   restraint_sum = restraint1 + restraint2 + restraint3 + ...
> That is, a restraint should be a value that you'd like to me made as
> small as possible, but can take either sign.  The restraints are
> simply appended to the "vector to be minimized" in the least squares
> sense.
> I'm not sure that will fully solve the issue of having different
> results between 10+ individual restraints and fewer summed restraints.
>    But I'm interested to hear and see more....

Given that individual restraints might be of either sign, you might
consider adding them in quadrature and using the square root of that
as the restraint.  As Matt said, the details matter, but I think that
would be a serviceable work around for more than 10 restraints.


 Bruce Ravel  ---------------------------------------------- bravel at anl.gov

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