On Friday 02 July 2004 01:00 pm, Jensen, Mark P. wrote:
Now this is where the whole approach might fail. I don't know if it is possible to to incorporate the delr or the delr+reff value from a specific feff path into an algebraic expressions in the Guess,Set,Def panel. Bruce or Matt or someone else will have to comment on this and explain how to do it. However, assuming that there is a straigforward way to do it, then...
Mark, The word "reff" is a very special word in ifeffit. It *always* evaluates to the effective path length (i.e. the length used in the feff calculation) of the path currently being evaluated. Thus, if you guess alpha 0 def dr alpha*reff then use "dr" as the deltaR path parameter math expression in a path, the value for that path's effective path length will be used even though the dr parameter was defined as a def. To say it another way, the above is equivalent to guess alpha 0 then using "alpha*reff" as the deltaR math expression later on. To say it yet another way, ifeffit's equation parser will recognize and correctly use the reff parameter regardless of how hard you try to obfuscate your math expressions. HTH, B -- Bruce Ravel ----------------------------------- ravel@phys.washington.edu Code 6134, Building 3, Room 405 Naval Research Laboratory phone: (1) 202 767 2268 Washington DC 20375, USA fax: (1) 202 767 4642 NRL Synchrotron Radiation Consortium (NRL-SRC) Beamlines X11a, X11b, X23b National Synchrotron Light Source Brookhaven National Laboratory, Upton, NY 11973 My homepage: http://feff.phys.washington.edu/~ravel EXAFS software: http://feff.phys.washington.edu/~ravel/software/exafs/