This script has been written by Rémi Khatib. Its goal is to treat the outputs of the vvaf program.

Behaviour

1. First it does an apodisation of the signal (filtering)
2. Then it does a Fourier transform

Compilation

gfortran -O2 filter.f95 -o filter

Using

Without input file (Just reply to the questions)

./filter

Launch it with an input file (check the example below)

./filter < input_filter

Remark about the outputs

1. The number of signals in the vvaf file (number of columns - 1) is associated with the number of block in the output file

2. Each block contains 6 columns:

• Frequency
• Real part of the FT
• Im part of the FT
• Im part of a Laplace transform (from 0 to $+\infty$ and from 0 to $-\infty$). This is really important for odd functions. This is what I use for the simulation of the SFG spectra.
• Norm of the FT
• Phase of the FT