On tight spans and tropical polytopes for directed distances

Hiroshi Hirai, Shungo Koichi

An extension $(V,d)$ of a metric space $(S,\mu )$ is a metric space with $S\subseteq V$ and $d{|}_S=\mu$, and is said to be tight if there is no other extension $(V,d^{\prime })$ of $(S,\mu )$ wit…