591058.fig.004a
(a)
591058.fig.004b
(b)
Figure 4: Comparison between HAM approximations (hollow symbols) and Runge-Kutta numerical solutions (solid lines) for 𝑟 ( 𝜏 ) (circles), 𝑟 ( 𝜏 ) (squares), and 𝑟 ( 𝜏 ) (stars); (a) 2nd-order approximation, (b) 5th-order approximation. The parameters for both the HAM and numerical solutions were set to: 𝜉 = 1 . 1 5 , 𝛼 = 1 , 𝜃 = 0 . 9 9 9 9 3 9 , = 2 . 3 .