Jump to content

Greater-than sign

From Wikipedia, the free encyclopedia
(Redirected from Greater than sign)
>
Greater-than sign
In UnicodeU+003E > GREATER-THAN SIGN (>, >)
Different from
Different fromU+232A RIGHT-POINTING ANGLE BRACKET
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

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 1631.[1] 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. The less-than sign and greater-than sign always "point" to the smaller number. 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.

History

[edit]

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.[1] The text states "Signum majoritatis ut a > b significet a majorem quam b (The sign of majority a > b indicates that a is greater than b)" and "Signum minoritatis ut a < b significet a minorem quam b (The sign of minority a < b indicates that a is less than 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,[1] in both backwards and forwards forms.[2] Johnson says it is likely Harriot developed the two symbols from this symbol.[2]

Usage in text markup

[edit]

Angle brackets

[edit]

The greater-than sign is sometimes used for an approximation of the closing angle bracket, . The proper Unicode character is U+232A RIGHT-POINTING ANGLE BRACKET. ASCII does not have angular brackets.

HTML

[edit]

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 Markdown

[edit]

In some early e-mail systems, the greater-than sign was used to denote quotations.[3] The sign is also used to denote quotations in Markdown.[4]

Usage in programming

[edit]

The 'greater-than sign' > is encoded in ASCII as character hex 3E, decimal 62. The Unicode code point is U+003E > GREATER-THAN SIGN, inherited from ASCII.

For use with HTML, the mnemonics &gt; or &GT; may also be used.

Programming language

[edit]

BASIC and C-family languages (including Java[5] and C++) use the comparison 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

[edit]

>> 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.[6]

Triple greater-than sign

[edit]

>>> is the unsigned-right-shift operator in JavaScript. Three greater-than signs form the distinctive 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 3.9.2 (default, Feb 20 2021, 18:40:11) 
[GCC 10.2.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> print("Hello World")
Hello World
>>>

Greater-than sign with equals sign

[edit]

>= is sometimes used for an approximation of the greater than or equal to sign, which was not included in the ASCII repertoire. The sign is, however, provided in Unicode, as U+2265 GREATER-THAN OR EQUAL TO (&ge;, &geq;, &GreaterEqual;).

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

[edit]

-> is used in some programming languages (for example F#) 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 PHP, this is used as a member access operator. In Swift and Python, it is used to indicate the return value type when defining a function (i.e., func foo() -> MyClass {...}).

Shell scripts

[edit]

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

[edit]

Greater-than sign is used in the 'spaceship operator', <=>.

ECMAScript and C#

[edit]

In ECMAScript and C#, the greater-than sign is used in lambda function expressions.

In ECMAScript:

const square = x => x * x;
console.log(square(5)); // 25

In C#:

Func<int, int> square = x => x * x;
Console.WriteLine(square(5)); // 25

PHP

[edit]

In PHP, the greater-than sign is used in conjunction with the less-than sign as a not equal to operator. It is the same as the != operator.

$x = 5;
$y = 3;
$z = 5;

echo $x <> $y; // true
echo $x <> $z; // false

Unicode

[edit]

In addition to U+003E > GREATER-THAN SIGN (&gt;, &GT;), Unicode provides various greater than symbols:[7]

Symbol Code Point Name
U+2369
Apl Functional Symbol Greater-Than Diaeresis
U+2344
Apl Functional Symbol Quad Greater-Than
U+29C1
Circled Greater-Than
U+2995
Double Left Arc Greater-Than Bracket
U+2A9A
Double-Line Equal To Or Greater-Than
U+2A9C
Double-Line Slanted Equal To Or Greater-Than
U+2AFA
Double-Line Slanted Greater-Than Or Equal To
U+2AA2
Double Nested Greater-Than
U+FF1E
Fullwidth greater than Sign
U+22DD
Equal To Or Greater-Than
U+2978
Greater-Than Above Rightwards Arrow
U+2A8E
Greater-Than Above Similar Or Equal
U+2A8A
Greater-Than And Not Approximate
U+2A88
Greater-Than And Single-Line Not Equal To
U+2269
Greater-Than But Not Equal To
U+22E7
Greater-Than But Not Equivalent To
U+2AA7
Greater-Than Closed By Curve
U+2AA9
Greater-Than Closed By Curve Above Slanted Equal
U+2A86
Greater-Than Or Approximate
U+2265
Greater-Than Or Equal To
U+2273
Greater-Than Or Equivalent To
U+2A7E
Greater-Than Or Slanted Equal To
U+2A82
Greater-Than Or Slanted Equal To With Dot Above
U+2A84
Greater-Than Or Slanted Equal To With Dot Above Left
U+2A80
Greater-Than Or Slanted Equal To With Dot Inside
U+2267
Greater-Than Over Equal To
> U+003E
Greater-Than Sign
U+2A7A
Greater-Than With Circle Inside
U+22D7
Greater-Than With Dot
U+2A7C
Greater-Than With Question Mark Above
U+226B
Much Greater-Than
U+2271
Neither Greater-Than Nor Equal To
U+2275
Neither Greater-Than Nor Equivalent To
U+226F
Not Greater-Than
U+2994
Right Arc Greater-Than Bracket
U+2AA0
Similar Above Greater-Than Above Equals Sign
U+2A9E
Similar Or Greater-Than
U+2A96
Slanted Equal To Or Greater-Than
U+2A98
Slanted Equal To Or Greater-Than With Dot Inside
U+FE65
Small greater than sign
U+2AF8
Triple Nested Greater-Than
U+22D9
Very Much Greater-Than

See also

[edit]

References

[edit]
  1. ^ a b c Smith, Charles L. (1964). "On the origin of ">" and "<"". The Mathematics Teacher. 57 (7): 479–481. doi:10.5951/MT.57.7.0479. ISSN 0025-5769. JSTOR 27957118. Archived from the original on 2022-06-05. Retrieved 2022-06-05.
  2. ^ a b Johnson, Art. "History of Mathematical Symbols". Classic Math: History Topics for the Classroom. Dale Seymour Publications, 1994.
  3. ^ Sherwood, Kaitlin Duck (22 October 1998). "A Beginner's Guide to Effective Email". www.webfoot.com. Archived from the original on 2021-10-14. Retrieved 2021-08-31.
  4. ^ "Markdown Syntax Cheatsheet". Lanna Digital. Archived from the original on 2021-08-31. Retrieved 2021-08-31.
  5. ^ "Summary of Operators". Oracle Corporation. Archived from the original on 16 April 2020. Retrieved 5 February 2020.
  6. ^ "XML Path Language (XPath) 2.0 (Second Edition)". www.w3.org. W3C. 14 December 2010. Archived from the original on 7 October 2022. Retrieved 29 October 2019.
  7. ^ "Greater than symbol". Archived from the original on 2023-05-18. Retrieved 2023-06-06.