In geometry, topology, and related branches of mathematics, a closed set is a set whose complement is an open set. In a topological space, a closed set can be defined as a set which contains all its limit points. In a complete metric space, a closed set is a set which is closed under the limit operation.
Read more about Closed Set: Equivalent Definitions of A Closed Set, Properties of Closed Sets, Examples of Closed Sets, More About Closed Sets
Famous quotes containing the words closed and/or set:
“We are closed in, and the key is turned
On our uncertainty;”
—William Butler Yeats (1865–1939)
“Racism is when you have laws set up, systematically put in a way to keep people from advancing, to stop the advancement of a people. Black people have never had the power to enforce racism, and so this is something that white America is going to have to work out themselves. If they decide they want to stop it, curtail it, or to do the right thing ... then it will be done, but not until then.”
—Spike Lee (b. 1956)