5. Appendices# 5.1. Fast Fourier Transform (FFT) Applied to FTIR Data 5.1.1. Phase Correction 5.1.2. Extracting the Sample Spectrum 5.1.3. Results 5.1.4. An Annotated Example 5.1.4.1. Loading CSV Data 5.1.4.2. Padding 5.1.4.3. Phase Extraction 5.1.4.4. Calculating the Spectrum 5.1.4.5. Calculating the Wavenumber Axis 5.1.4.6. Apodization