Implementing Formula in LabView

I seem to have a rather odd problem. I just can't figure out why isn't a certain calculation (refractive index) working properly.
Background info: I measured a high purity silicon plate using an instrument (THz-TDS), suffice it to say that the formulae for calculating refractive index from my raw data is very well established and published. But when I implement this formulae in Labview and run it, I don't get the expected result for
silicon (the published refractive index for high purity silicon is around 3.45), instead I get values around 1.
Any ideas or explanations on what I'm doing wrong are appreciated.
Attached files:
3 VI's where one is the Main. On the Main VI just load the two *.dat files provided and type 0.00198 for sample (silicon) thickness and it should run.
Attached is also the formulae in *.jpeg format.
and a *.doc showing the correct ref. index graph for silicon. Unfortunately I don't have the matlab code that this was originally done from.
Thanks again
Kas
Attachments:
To Post.zip ‏67 KB

I actually tried that but with no luck.
There is one thing I'm curious.
there is a line code in MatLab called: phas1=unwrap(angle(z_face1),pi).
Is that the same this as "theta" from the polar form of FFT?
I made few phone calls and managed to get the MatLab code that calculated ref. index. Attached is the code.
He didn't seem to have implemented the formulae as he should've. But he claimed he had various other samples measured and got the correct answer with this routine.
Again, I tried implementing the same routine but no luck.
is it possible to convert this MatLab into LabView code in a more efficient manner. I might have made a mistake translating from one language to another.
Thanks again
Kas
Attachments:
MatLab Code.txt ‏2 KB

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