Definition:Reversed Contour
Definition
Let $\R^n$ be a real cartesian space of $n$ dimensions.
Let $C$ be a contour in $\R^n$.
Then $C$ is defined as a concatenation of a finite sequence $C_1, \ldots, C_n$ of directed smooth curves in $\R^n$.
The reversed contour of $C$ is denoted $-C$ and is defined as the concatenation of the finite sequence:
- $-C_n, -C_{n - 1}, \ldots, -C_1$
where $-C_i$ is the reversed directed smooth curve of $C_i$ for all $i \in \set {1, \ldots, n}$.
Complex Plane
The definition carries over to the complex plane, in which context it is usually applied:
Let $C$ be a contour in the complex plane $\C$.
Then $C$ is defined as a concatenation of a finite sequence $\sequence {C_1, \ldots, C_n}$ of directed smooth curves in $\C$.
The reversed contour of $C$ is denoted $-C$ and is defined as the concatenation of the finite sequence:
- $-C_n, -C_{n-1}, \ldots, -C_1$
where $-C_k$ is the reversed directed smooth curve of $C_k$ for all $i \in \set {1, \ldots, n}$.
Also denoted as
The reversed contour of $C$ is denoted as $C^-$ in some texts.
Also see
- Reversed Contour is Contour: demonstration that this defines a contour.
Sources
- 2001: Christian Berg: Kompleks funktionsteori: $\S 2.2$