Metric projection and convergence theorems for nonexpansive mappings in Hadamard spaces

Hossein Dehghan, Jamal Rooin

For a nonempty convex subset $C$ of a Hadamard space $X$, it is proved that $u=P_{C}x$ if and only if $⟨\overrightarrow{xu},\overrightarrow{uy}⟩⩾0$ for all $y\in…