freal	Specific spatial frequency of the real machined surface
fs	Feed rate (mm/min)
fsimulated	Specific spatial frequency of the simulated machined surface
i	Index for the tool tip position along the trajectory
j	Index for the point of the surface height profile
PV	Maximum peak-to-valley value (nm)
R	Distance from the tool tip position to the center of the workpiece
R 0	Radius of the workpiece
Ra	Arithmetic roughness (nm)
radt	Tool nose radius (mm)
Sa	Arithmetic surface roughness (nm)
ss	Feed rate per revolution of the workpiece (mm/rev)
t	Machining time (s)
Xi	x coordinate of the tool tip position
Yi	y coordinate of the tool tip position
zj	Height of jth point of the profile
zmean	Mean height of the surface profile
θi	ith tool tip position of the tool in the trajectory
ω	Rotational speed (rad/s)