Editing Domain of a function (section)

== Other uses ==

The term ''domain'' is also commonly used in a different sense in [[mathematical analysis]]: a ''[[Domain (mathematical analysis)|domain]]'' is a [[empty set|non-empty]] [[connected (topology)|connected]] [[open set]] in a [[topological space]]. In particular, in [[real analysis|real]] and [[complex analysis]], a ''domain'' is a non-empty connected open subset of the [[real coordinate space]] <math>\R^n</math> or the [[complex coordinate space]] <math>\C^n.</math>

Sometimes such a domain is used as the domain of a function, although functions may be defined on more general sets. The two concepts are sometimes conflated as in, for example, the study of [[partial differential equation]]s: in that case, a ''domain'' is the open connected subset of <math>\R^{n}</math> where a problem is posed, making it both an analysis-style domain and also the domain of the unknown function(s) sought.