Greater-than sign

The greater-than sign is a mathematical symbol that denotes an inequality between two values. The widely adopted form of two equal-length strokes connecting in an acute angle at the right, >, has been found in documents dated as far back as the 1560s. In typical mathematical usage, the greater-than sign is typically placed between the two values being compared and signals that the first number is greater than the second number. Examples of typical usage include 1½ > 1 and 1 > −2. Since the development of computer programming languages, the greater-than sign and the less-than sign have been repurposed for a range of uses and operations.

Greater-than sign

History

The symbols < and > first appear in Artis Analyticae Praxis ad Aequationes Algebraicas Resolvendas (‘The Analytical Arts Applied to Solving Algebraic Equations’) by Thomas Harriot (1560–1621), which was published posthumously in 1631. The text states: "Signum majoritatis ut a > b significet a majorem quam b" and "Signum minoritatis ut a < b significet a minorem quam b."

According to Johnson (page 144), while Harriot was surveying North America, he saw a Native American with a symbol that resembled the greater-than sign both backwards and forwards ( > and < ).[1] Johnson says it is likely he developed the two symbols from this symbol.[1]

Computing

The greater-than sign (>) is an original ASCII character (hex 3E, decimal 62).

The character in Unicode is U+003E > GREATER-THAN SIGN (HTML &#62; · &gt;); this is inherited from the same value in ASCII.

Apart from this, Unicode also has the following variants:

Angle brackets

The greater-than sign is used for an approximation of the closing angle bracket (⟩). ASCII does not have angular brackets.

Programming language

BASIC and C-family languages, (including Java and C++) use the operator > to mean "greater than". In Lisp-family languages, > is a function used to mean "greater than". In Coldfusion and Fortran, operator .GT. means "greater than".

Double greater-than sign

The double greater-than sign (>>) is used for an approximation of the much greater than sign (≫). ASCII does not have the much greater-than sign.

The double greater-than sign (>>) is also used for an approximation of the closing guillemet (»).

In Java, C, and C++, the operator >> is the right-shift operator. In C++ it is also used to get input from a stream, similar to the C functions getchar and fgets.

In Haskell, the >> function is a monadic operator. It is used for sequentially composing two actions, discarding any value produced by the first. In that regard, it is like the statement sequencing operator in imperative languages, such as the semicolon in C.

Triple greater-than sign

The triple greater-than sign (>>>) is the unsigned right shift operator in JavaScript, and is the default Python prompt of the interactive shell, often seen for code examples which can be executed interactively in the interpreter- project-dir

~:$ python
Python 2.7.5 (default, Mar  9 2014, 22:15:05) 
[GCC 4.2.1 Compatible Apple LLVM 5.0 (clang-500.0.68)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> print("Hello World")
Hello World
>>>

Greater-than sign with equals sign

The greater-than sign plus the equals sign (>=) is used for an approximation of the greater than or equal to sign (≥). ASCII doesn't have a greater-than-or-equal-to sign.

In BASIC, Lisp-family languages, and C-family languages (including Java and C++), operator >= means "greater than or equal to". In Sinclair BASIC it is encoded as a single-byte code point token.

In Fortran, operator .GE. means "greater than or equal to".

In Bourne shell and Windows PowerShell, the operator -ge means "greater than or equal to".

Hyphen-minus with greater-than sign

In some programming languages (for example F#), the greater-than sign is used in conjunction with a hyphen-minus to create an arrow (->). Arrows like these could also be used in text where other arrow symbols are unavailable.

Shell scripts

In Bourne shell (and many other shells), greater-than sign is used to redirect output to a file. Greater-than plus ampersand (>&) is used to redirect to a file descriptor.

Spaceship operator

Greater-than sign is used in the spaceship operator.

HTML

In HTML (and SGML and XML), the greater-than sign is used at the end of tags. The greater-than sign may be included with &gt;, while &ge; produces the greater-than or equal to sign.

Electronic mail

The greater-than sign is used to denote quotations in the e-mail and newsgroup formats, and this has been taken into use also in forums.

Texting (SMS), online chat

The greater-than sign is used to express the act (or intent) of rubbing noses, typically in an affectionate or playful manner, with the recipient of the text/instant message.

See also

References

  1. 1 2 "Earliest Uses of Symbols of Relation". jeff560.tripod.com. Last updated: Nov. 11, 2011.
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