Deepak, 

The data files you sent appear to be plots of XAFS |chi(R)|, including offsets for the plotting.  That is certainly a reasonable visualization to make for EXAFS data and Demeter can make those easily. 

But |chi(R)| is not a histogram of the number of atoms as a function of distance.  That is sort of all of "EXAFS analysis" and unfortunately there is not a simple transform that converts |chi(R)| into g(R).   I recommend looking at some of the on-line resources and books and review articles on EXAFS.  

Cheers,

--Matt