Start: go to the homepage U+2190 bis U+21FF Arrows
Zeichen für U+21A0
Quelle: Noto Sans Math

U+21A0 Rightwards Two Headed Arrow

U+21A0 wurde in Version 1.1 in 1993 zu Unicode hinzugefügt. Er gehört zum Block U+2190 bis U+21FF Arrows in der U+0000 bis U+FFFF Basic Multilingual Plane.

Dieses Zeichen ist ein Math Symbol und wird allgemein verwendet, das heißt, in keiner speziellen Schrift. Das Schriftzeichen ist auch bekannt als z notation total surjection und fast cursor right.

Das Zeichen ist keine Zusammensetzung. Es hat keine zugewiesene Weite in ostasiatischen Texten. In bidirektionalem Text handelt es als Other Neutral. Bei einem Richtungswechsel wird es nicht gespiegelt. Das Wort, das U+21A0 mit ähnlichen Zeichen bildet, verbietet in sich Zeilenumbrüche. Der Buchstabe kann mit einem anderen Zeichen verwechselt werden.

Das CLDR-Projekt bezeichnet dieses Zeichen mit „Pfeil mit Doppelspitze nach rechts“ für die Verwendung in Screenreader-Software.

Die Wikipedia hat die folgende Information zu diesem Codepunkt:

In mathematics, a surjective function (also known as surjection, or onto function ) is a function f such that, for every element y of the function's codomain, there exists at least one element x in the function's domain such that f(x) = y. In other words, for a function f : XY, the codomain Y is the image of the function's domain X. It is not required that x be unique; the function f may map one or more elements of X to the same element of Y.

The term surjective and the related terms injective and bijective were introduced by Nicolas Bourbaki, a group of mainly French 20th-century mathematicians who, under this pseudonym, wrote a series of books presenting an exposition of modern advanced mathematics, beginning in 1935. The French word sur means over or above, and relates to the fact that the image of the domain of a surjective function completely covers the function's codomain.

Any function induces a surjection by restricting its codomain to the image of its domain. Every surjective function has a right inverse assuming the axiom of choice, and every function with a right inverse is necessarily a surjection. The composition of surjective functions is always surjective. Any function can be decomposed into a surjection and an injection.

Darstellungen

System Darstellung
Nr. 8608
UTF-8 E2 86 A0
UTF-16 21 A0
UTF-32 00 00 21 A0
URL-kodiert %E2%86%A0
HTML hex reference ↠
Falsches windows-1252-Mojibake ↠
HTML named entity ↠
HTML named entity ↠
Alias z notation total surjection
Alias fast cursor right
Kodierung: GB18030 (Hex-Bytes) 81 36 C8 30
LATEX \twoheadrightarrow

Verwandte Schriftzeichen

Verwechselbare

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Vollständiger Eintrag

Eigenschaft Wert
Alter (age) 1.1 (1993)
Unicode-Name (na) RIGHTWARDS TWO HEADED ARROW
Unicode-1-Name (na1) RIGHT TWO HEADED ARROW
Block (blk) Arrows
Allgemeine Kategorie (gc) Math Symbol
Schrift (sc) Common
Bidirectional Category (bc) Other Neutral
Combining Class (ccc) Not Reordered
Dekompositionstyp (dt) none
Decomposition Mapping (dm) Zeichen für U+21A0 Rightwards Two Headed Arrow
Kleinbuchstabe (Lower)
Simple Lowercase Mapping (slc) Zeichen für U+21A0 Rightwards Two Headed Arrow
Lowercase Mapping (lc) Zeichen für U+21A0 Rightwards Two Headed Arrow
Großbuchstabe (Upper)
Simple Uppercase Mapping (suc) Zeichen für U+21A0 Rightwards Two Headed Arrow
Uppercase Mapping (uc) Zeichen für U+21A0 Rightwards Two Headed Arrow
Simple Titlecase Mapping (stc) Zeichen für U+21A0 Rightwards Two Headed Arrow
Titlecase Mapping (tc) Zeichen für U+21A0 Rightwards Two Headed Arrow
Case Folding (cf) Zeichen für U+21A0 Rightwards Two Headed Arrow
ASCII Hex Digit (AHex)
Alphabetic (Alpha)
Bidi-Kontrollzeichen (Bidi_C)
Bidi Mirrored (Bidi_M)
Composition Exclusion (CE)
Case Ignorable (CI)
Changes When Casefolded (CWCF)
Changes When Casemapped (CWCM)
Changes When NFKC Casefolded (CWKCF)
Changes When Lowercased (CWL)
Changes When Titlecased (CWT)
Changes When Uppercased (CWU)
Cased (Cased)
Full Composition Exclusion (Comp_Ex)
Default Ignorable Code Point (DI)
Dash (Dash)
Veraltet (Dep)
Diakritisch (Dia)
Emoji Modifier Base (EBase)
Emoji Component (EComp)
Emoji Modifier (EMod)
Emoji-Darstellung (EPres)
Emoji (Emoji)
Extender (Ext)
Extended Pictographic (ExtPict)
FC NFKC Closure (FC_NFKC) Zeichen für U+21A0 Rightwards Two Headed Arrow
Grapheme Cluster Break (GCB) Egal
Grapheme Base (Gr_Base)
Grapheme Extend (Gr_Ext)
Grapheme Link (Gr_Link)
Hex Digit (Hex)
Hyphen (Hyphen)
ID Continue (IDC)
ID-Start (IDS)
IDS Binary Operator (IDSB)
IDS Trinary Operator and (IDST)
IDSU (IDSU) 0
ID_Compat_Math_Continue (ID_Compat_Math_Continue) 0
ID_Compat_Math_Start (ID_Compat_Math_Start) 0
Ideogramm (Ideo)
InCB (InCB) None
Indic Mantra Category (InMC)
Indic Positional Category (InPC) NA
Indic Syllabic Category (InSC) Other
Jamo Short Name (JSN)
Verbindungskontrollzeichen (Join_C)
Logische Reihenfolgenausnahme (LOE)
Modifier Combining Mark (MCM)
Math (Math)
Nicht-Zeichen-Codepunkt (NChar)
NFC Quick Check (NFC_QC) Ja
NFD Quick Check (NFD_QC) Ja
NFKC Casefold (NFKC_CF) Zeichen für U+21A0 Rightwards Two Headed Arrow
NFKC Quick Check (NFKC_QC) Ja
NFKC_SCF (NFKC_SCF) Zeichen für U+21A0 Rightwards Two Headed Arrow
NFKD Quick Check (NFKD_QC) Ja
Other Alphabetic (OAlpha)
Other Default Ignorable Code Point (ODI)
Other Grapheme Extend (OGr_Ext)
Other ID Continue (OIDC)
Other ID Start (OIDS)
Other Lowercase (OLower)
Other Math (OMath)
Other Uppercase (OUpper)
Prepended Concatenation Mark (PCM)
Pattern Syntax (Pat_Syn)
Pattern White Space (Pat_WS)
Quotation Mark (QMark)
Regional Indicator (RI)
Radical (Radical)
Sentence Break (SB) Andere
Soft Dotted (SD)
Sentence Terminal (STerm)
Terminal Punctuation (Term)
Unified Ideograph (UIdeo)
Variation Selector (VS)
Word Break (WB) Andere
White Space (WSpace)
XID Continue (XIDC)
XID-Start (XIDS)
Expands On NFC (XO_NFC)
Expands On NFD (XO_NFD)
Expands On NFKC (XO_NFKC)
Expands On NFKD (XO_NFKD)
Bidi Paired Bracket (bpb) Zeichen für U+21A0 Rightwards Two Headed Arrow
Bidi Paired Bracket Type (bpt) None
Ostasiatische Weite (ea) neutral
Hangul Syllable Type (hst) Nicht anwendbar
ISO 10646 Comment (isc)
Joining Group (jg) No_Joining_Group
Joining Type (jt) Non Joining
Line Break (lb) Alphabetic
Numerischer Typ (nt) none
Numerischer Wert (nv) keine Nummer
Simple Case Folding (scf) Zeichen für U+21A0 Rightwards Two Headed Arrow
Schrifterweiterung (scx)
Vertical Orientation (vo) R