Recently, I studied a paper called What Does Your Chair Know About Your Stress Level?It can be download at the link below.http://www.barnrich.ch/wiki/data/media/pub/2010_what_does_your_chair_know_about_your_stress_level.pdfat page 210, Fig.5 (picture 5) mentioned thatSpectra of the norm of the CoP vector during the experiment (stages 37) for the same subject used in Fig. 4.How did they do to transform Fig.4 to Fig.5? And what do x-axis and y-axis mean in Fig.5?Fig4Fig5
How to transform one graph to a spectrum?
machine learning