[Ifeffit] non-monotonic data

[Bruce Ravel]

Matt,

Can you explain what ifeffit does when it reads a mu(E) data file
which has non-monotonically increasing energy values.  Specifically
what happens to data like this:

   # energy    xmu
   # ----------------
       1        0.1
       2        0.15 
       2        0.15 
       3        0.18
       4        0.2

end so on.

Ifeffit throws up one of these two sets of error messages:
   spline:   energy data appears out of order
   pre_edge: energy data appears out of order
or
   spline: energy and xmu are different length?

I understand that non-monotonic data will give problems in the
intepolations and elsewhere, but what does ifeffit actually do in this
case?

FWIW, I plan to have athena check data as it is read in to verify that
the energy array is monotonic up (or down, in which case the data will
be reversed) before trying to do anything with it.  But I remain
curious about what ifeffit chooses to do.

B


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