“…Applications appear in various areas, including computer vision [31], machine learning [34], maximum likelihood estimation [45,56], electronic structure computation [30], system balancing [19], model reduction [57], and robot manipulation [18]. A lot of algorithms such as steepest descent method, trust-region method, conjugate gradient method and so on have been extended to solve optimization problems on Riemannian manifolds (see, e.g., [1,23,46,47] and the references therein).…”