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)
“I set out as a sort of self-dependent politician. My opinions were my own. I dashed at all prejudices. I scorned to follow anybody in matter of opinion.... All were, therefore, offended at my presumption, as they deemed it.”
—William Cobbett (1762–1835)