Table 1. Variables obtained from CoP and codes to calculate in Matlab.

Variables	Matlab codes
Anteroposterior displacements	$\mathrm{CoP}\mathrm{ap}=\mathrm{filtfilt}\left(b,a,\mathrm{file}\left(:,2\right)\right)110;$
	$\mathrm{CoP}\mathrm{AP}=\left(\max \left(\mathrm{CoP}\mathrm{ap}\right)-\min \left(\mathrm{CoP}\mathrm{ap}\right)\right);$
Mediolateral displacements	$\mathrm{CoP}\mathrm{ml}=\mathrm{filtfilt}\left(b,a,\mathrm{file}\left(:,1\right)\right)\mathrm{./}10;$
	$\mathrm{CoP}\mathrm{ML}=\left(\max \left(\mathrm{CoP}\mathrm{ml}\right)-\min \left(\mathrm{CoP}\mathrm{ml}\right)\right);$
Total displacements	$\mathrm{DOT}=\mathrm{sum}\left(\mathrm{sqrt}\left(\left(\mathrm{CoP}\mathrm{AP}.^2\right)+\left(\mathrm{CoP}\mathrm{ML}.^2\right)\right)\right);$
Total velocity	$\mathrm{TotalVel}=\mathrm{sum}\left(\mathrm{sqrt}\left(\mathrm{diff}\left(\mathrm{CoP}\mathrm{AP}\right).^2+\mathrm{diff}\left(\mathrm{CoP}\mathrm{ML}\right).^2\right)\right)★\raisebox{1ex}{$\mathrm{freq}$}\!\left/ \!\raisebox{-1ex}{$\mathrm{length}$}\right.\left(\mathrm{CoP}\mathrm{AP}\right);$
Elliptical Area 95%	$\left[\mathrm{vec},\mathrm{vall}=\mathrm{eig}\left(\mathrm{cov}\left(\mathrm{CoP}\mathrm{AP},\mathrm{CoP}\mathrm{ML}\right)\right)\right.;$
	$\mathrm{EA}=\mathrm{pi}★\mathrm{prod}\left(2.4478★\mathrm{sqrt}\left(\mathrm{svd}\left(\mathrm{vall}\right)\right)\right);$