Aha. so I kind of found a solution myself: the problem was assigning 1 and 2 when importing the spectrum. It wasn't clear to me that numerator had to be set to 1 when energy is column one. Now seems to work. 
Sorry to bother you. 
y.

On Mon, Mar 2, 2015 at 3:15 PM, <kirshstein@gmail.com> wrote:
Hello, 

I have just installed Demeter and the first thing Athena does, when asked to plot (mu(E)) of an averaged standard spectrum (S-K-edge of CaSO4, averaged in sixpack), is to give the following error message: 
"Use of uninitialized value in multiplication(*) at C:/strawberry/perl/site/lib/Math/Spline.pm line 36." 

Also E0 is 0 and in front of a red background. So it seems to have trouble finding E0. But why? 

What does this mean? What do I have to do to get athena to work? 

attached is the CaSO4 spectrum in question. 

Thanks! 

Yael Kirsch