[Ifeffit] graphics and fit

[Bruce Ravel]

On Thursday 13 May 2004 10:08 am, Stefano Ciurli wrote:
> I also posed a question regarding the possibility to treat an
> imidazole ring as a rigid object, like Excurve is able to do. Any
> ideas? I am sure someone in the list working on biological samples
> and using feff has some nice input files for a histidine bound to a
> metal, with the file usable in a rigid body fit...

While this is certainly not (yet) automated in Artemis, there is
certainly no reason that Ifeffit cannot be coerced into treating a
histadine (or, indeed, and other structure) in this manner.

delta_R for a path is represented by an arbitrary math expression and
these math expressions can include any constraint that you, the user,
can imagine.  So, it is certainly within the capabilities of
Artemis/Ifeffit to treat a group of paths in this manner.  It's "no
more than" a matter of doing some geometry and then writing the
delta_R math expressions that solve those geometry problems.

That may not be trivial, but it certainly isn't unfathomably difficult
either.  To borrow from the slogan of the perl programming language,
"Ifeffit makes hard things possible."

B

-- 
 Bruce Ravel  ----------------------------------- ravel at phys.washington.edu
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