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 mathematical writing, the greater-than sign is typically placed between two values being compared and signifies that the first number is greater than the second number. Examples of typical usage include 1.5 > 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
In UnicodeU+003E > GREATER-THAN SIGN (HTML > · >, >)
Related
See alsoU+2265 GREATER-THAN OR EQUAL TO

U+2A7E GREATER-THAN OR SLANTED EQUAL TO

U+226F NOT GREATER-THAN
U+226B MUCH GREATER-THAN
Different from
Different fromU+232A RIGHT-POINTING ANGLE BRACKET

History

The earliest known use of the symbols < and > is found in Artis Analyticae Praxis ad Aequationes Algebraicas Resolvendas (The Analytical Arts Applied to Solving Algebraic Equations) by Thomas Harriot, 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 historian Art Johnson, while Harriot was surveying North America, he saw a Native American with a symbol that resembled the greater-than sign, in both backwards and forwards forms.[1] Johnson says it is likely Harriot developed the two symbols from this symbol.[1]

Computing

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

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

Angle brackets

The greater-than sign is sometimes used for an approximation of the closing angle bracket, (or "upright chevron"). The proper Unicode character is U+232A RIGHT-POINTING ANGLE BRACKET (HTML &#9002;). ASCII does not have angular brackets.

Programming language

BASIC and C-family languages (including Java[2] 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.

In XPath the >> operator returns true if the left operand follows the right operand in document order; otherwise it returns false.[3]

Triple greater-than sign

The triple greater-than sign, >>>, is the unsigned-right-shift operator in JavaScript. Three greater-than signs form the distinctive "three chevron prompt" of the firmware console in MicroVAX, VAXstation, and DEC Alpha computers (known as the SRM console in the latter). This is also the default prompt of the Python interactive shell, often seen for code examples that can be executed interactively in the interpreter:

~:$ 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 does not 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".

In Lua, operator >=means "greater than or equal to" and is used like this

x = math.random(1,9)
y = 5
if x >= y then
    print("x("..x..") is more or equal to y("..y..")")
else
    print("x("..x..") is less than y("..y..")")
end

expected output: x(number >= 5) is more or equal to y(5) or x(number < 5) is less than y(5)

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. In the R programming language, this can be used as the right assignment operator. In the C, C++, and C# programming languages, this is used as a member access operator. In Swift, it is used to indicate the return value type when defining a function (i.e., func foo() -> MyClass {...}).

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.

E-mail and the Internet

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. It is also used before a sentence for a sense of implication. (>implying)

See also

References

  1. Johnson, Art. "History of Mathematical Symbols". Classic Math: History Topics for the Classroom. Dale Seymour Publications, 1994.
  2. "Summary of Operators". docs.oracle.com. Retrieved 5 February 2020.
  3. "XML Path Language (XPath) 2.0 (Second Edition)". www.w3.org. W3C. 14 December 2010. Retrieved 29 October 2019.
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