Appaloosa (film) Appaloosa (film) Appaloosa is a 2008 American Western film based on the 2005 novel "Appaloosa" by crime writer Robert B. Parker. Directed by Ed Harris and co-written by Harris and Robert Knott, "Appaloosa" stars Harris alongside Viggo Mortensen, Renée Zellweger and Jeremy Irons. The film premiered at 2008 Toronto International Film Festival and was released in selected cities on September 19, 2008, then expanded into wide-release on October 3, 2008. The film shares some narrative similarities with the 1959 Western "Warlock", directed by Edward Dmytryk and starring Henry Fonda, Anthony Quinn and Richard Widmark. There is also a 1966 Western
Directed set While the definition of a directed set is for an "upward-directed" set (every pair of elements has an upper bound), it is also possible to define a downward-directed set in which every pair of elements has a common lower bound. A subset of a poset is downward-directed if and only if its upper closure is a filter. Directed subsets are used in domain theory, which studies directed complete partial orders. These are posets in which every upward-directed set is required to have a least upper bound. In this context, directed subsets again provide a generalization of convergent sequences. Directed set