Close  
Figure 2: Principal component analysis coefficients of nine deformation vector fields of prior fourdimensionalcomputed tomography. From top to bottom, the principal component analysis coefficients (w1, w2, and w3) correspond to deformable field vectors along different directions (superoinferior, anteroposterior, and lateral). From left to right, the principal component analysis coefficients correspond to the first three primary principal components. The Xaxis represents the phase number of the nine deformation vector fields used to calculate principal component analysis coefficients 
