U+2A13 "⨓" Line Integration with Semicircular Path Around Pole Unicode Character

U+2A13 "⨓" Line Integration with Semicircular Path Around Pole is a mathematical symbol used in complex analysis to denote a specific type of contour integral. In this notation, the integration path consists of a straight line segment that approaches a singularity, combined with a semicircular detour that goes around a pole to avoid it, often as part of a larger closed contour for evaluating integrals via the residue theorem. The symbol compactly represents the process of integrating along a line while circumventing a point where the function is not analytic, making it a valuable tool for expressing calculations in physics and engineering, particularly in the study of Fourier transforms and Cauchy principal value integrals.

General Properties

Code Point	U+2A13
Version Added	3.2
Name	Line Integration with Semicircular Path Around Pole
Block	Supplemental Mathematical Operators
General Category	Math Symbol
Canonical Combining Class	Not Reordered
Bidirectional Class	Other Neutral
Mirrored	Yes

Encodings

HTML Decimal Encoding	⨓
HTML Hex Encoding	⨓
UTF-8 Encoding	0xE2 0xA8 0x93
UTF-16 Encoding	0x2A13
UTF-32 Encoding	0x00002A13
C/C++/Java Escape	\u2a13

Unicode Properties

NFC Quick Check	Yes
NFD Quick Check	Yes
NFKC Quick Check	Yes
NFKD Quick Check	Yes
Numeric Type	None
Numeric Value	NaN
Line Break	Alphabetic
Script	Common
Script Extensions	Common
Indic Syllabic Category	Other
Pattern Syntax	Yes
Math	Yes
Vertical Orientation	Rotated
Grapheme Base	Yes
Grapheme Cluster Break	Other
Word Break	Other
Sentence Break	Other