# [Ifeffit] maximum argument length?

Peter Southon p.southon at usyd.edu.au
Mon Dec 22 22:11:39 CST 2003

```Hello all,

Is there a limit on the total length of arguments that follow an Ifeffit
command? If so, is there a way of expanding the limit?

I've constructed a rather complicated model which uses 37 paths (mostly
multiple scattering). Furthermore, quite a few of these paths are sensitive
to scattering angle, so I have calculated FEFF files for three versions
each of most paths (each for a different scattering angle), as suggested in
the course "EXAFS Analysis with FEFF and FEFFIT" and the old Feffit manual.
Thus the final Ifeffit command calls on a lot of FEFF paths, each
specifically numbered according to path and angle.
Unfortunately, after adding a few extra paths I get error messages when
running the feffit command: "feffit:unknown key" followed by a list of
paths about halfway through my list, and also "feffit: no chi(k) data
array?". I assume that this is because ifeffit will only swallow half the
command, which is:

feffit(1-4,500,510,520,600,610,620,700,710,720,800,810,820,
9-13,15-16,1700,1710,1720,1800,1810,1820,1900,1910,1920,2000,2010,2020,
37, 3800,3810,3820,3900,3910,3920,4000,4010,4020,4100,4110,4120,
4200,4210,4220,4300,4310,4320,4400,4410,4420,4500,4510,4520,
4600,4610,4620,4700,4710,4720,4800,4810,4820,4900,4910,4920,
5000,5010,5020,5100,5110,5120,5200,5210,5220,5300,5310,5320,
5400,5410,5420,5500,5510,5520,
chi = data15.chi, macro = plot_fit)

Short of actually renumbering all my paths so that they run sequentially,
is there any solution...?

Have a merry Christmas,

Peter

Peter Southon
Research Fellow - School of Chemistry
University of Sydney, NSW 2006, Australia
+61 2 9351 4425

```