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74-414: The PARI/GP system is a package that is capable of doing formal computations on recursive types at high speed; it is primarily aimed at number theorists. Its three main strengths are its speed, the possibility of directly using data types that are familiar to mathematicians , and its extensive algebraic number theory module. The PARI/GP system consists of the following standard components: Also available

148-434: A data type (or simply type ) is a collection or grouping of data values , usually specified by a set of possible values, a set of allowed operations on these values, and/or a representation of these values as machine types. A data type specification in a program constrains the possible values that an expression , such as a variable or a function call, might take. On literal data, it tells the compiler or interpreter how

222-402: A structured programming model would tend to not include code, and are called plain old data structures . Data types may be categorized according to several factors: The terminology varies - in the literature, primitive, built-in, basic, atomic, and fundamental may be used interchangeably. All data in computers based on digital electronics is represented as bits (alternatives 0 and 1) on

296-421: A to forall r. (forall a. f a -> r) -> r or a similar type. A refinement type is a type endowed with a predicate which is assumed to hold for any element of the refined type. For instance, the type of natural numbers greater than 5 may be written as { n ∈ N | n > 5 } {\displaystyle \{n\in \mathbb {N} \,|\,n>5\}} A dependent type

370-505: A . However, maintaining the validity of this equation means that while the result of a%b is, as expected, in the half-open interval [0, b ), where b is a positive integer, it has to lie in the interval ( b , 0] when b is negative. Python provides a round function for rounding a float to the nearest integer. For tie-breaking , Python 3 uses round to even : round(1.5) and round(2.5) both produce 2 . Versions before 3 used round-away-from-zero : round(0.5)

444-419: A certain type. Python does not support tail call optimization or first-class continuations , and, according to Van Rossum, it never will. However, better support for coroutine -like functionality is provided by extending Python's generators . Before 2.5, generators were lazy iterators ; data was passed unidirectionally out of the generator. From Python 2.5 on, it is possible to pass data back into

518-644: A combination of reference counting and a cycle-detecting garbage collector for memory management . It uses dynamic name resolution ( late binding ), which binds method and variable names during program execution. Its design offers some support for functional programming in the Lisp tradition. It has filter , map and reduce functions; list comprehensions , dictionaries , sets, and generator expressions. The standard library has two modules ( itertools and functools ) that implement functional tools borrowed from Haskell and Standard ML . Its core philosophy

592-597: A corresponding native type does not exist on the target platform, the compiler will break them down into code using types that do exist. For instance, if a 32-bit integer is requested on a 16 bit platform, the compiler will tacitly treat it as an array of two 16 bit integers. Floating point data types represent certain fractional values ( rational numbers , mathematically). Although they have predefined limits on both their maximum values and their precision, they are sometimes misleadingly called reals (evocative of mathematical real numbers ). They are typically stored internally in

666-420: A decrease in indentation signifies the end of the current block. Thus, the program's visual structure accurately represents its semantic structure. This feature is sometimes termed the off-side rule . Some other languages use indentation this way; but in most, indentation has no semantic meaning. The recommended indent size is four spaces. Python's statements include: The assignment statement ( = ) binds

740-561: A family of function types differentiated by argument and return types, such as the type Int -> Bool denoting functions taking an integer and returning a Boolean. In C, a function is not a first-class data type but function pointers can be manipulated by the program. Java and C++ originally did not have function values but have added them in C++11 and Java 8. A type constructor builds new types from old ones, and can be thought of as an operator taking zero or more types as arguments and producing

814-510: A generator function; and from version 3.3, it can be passed through multiple stack levels. Python's expressions include: In Python, a distinction between expressions and statements is rigidly enforced, in contrast to languages such as Common Lisp , Scheme , or Ruby . This leads to duplicating some functionality. For example: Statements cannot be a part of an expression—so list and other comprehensions or lambda expressions , all being expressions, cannot contain statements. A particular case

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888-475: A language-defined machine representation. The C programming language , for instance, supplies types such as Booleans, integers, floating-point numbers, etc., but the precise bit representations of these types are implementation-defined. The only C type with a precise machine representation is the char type that represents a byte. The Boolean type represents the values true and false . Although only two values are possible, they are more often represented as

962-428: A large body of existing code could not easily be forward-ported to Python 3. No further security patches or other improvements will be released for it. While Python 2.7 and older versions are officially unsupported, a different unofficial Python implementation, PyPy , continues to support Python 2, i.e. "2.7.18+" (plus 3.10), with the plus meaning (at least some) " backported security updates". Python 3.0

1036-445: A matrix‑multiplication operator @ . These operators work like in traditional math; with the same precedence rules , the operators infix ( + and - can also be unary to represent positive and negative numbers respectively). The division between integers produces floating-point results. The behavior of division has changed significantly over time: In Python terms, / is true division (or simply division ), and //

1110-402: A name as a reference to a separate, dynamically allocated object . Variables may subsequently be rebound at any time to any object. In Python, a variable name is a generic reference holder without a fixed data type ; however, it always refers to some object with a type. This is called dynamic typing —in contrast to statically-typed languages, where each variable may contain only a value of

1184-461: A new and improved interactive interpreter ( REPL ), featuring multi-line editing and color support; an incremental garbage collector (producing shorter pauses for collection in programs with a lot of objects, and addition to the improved speed in 3.11 and 3.12), and an experimental just-in-time (JIT) compiler (such features, can/needs to be enabled specifically for the increase in speed), and an experimental free-threaded build mode, which disables

1258-419: A numeric string, such as "1234" . These numeric strings are usually considered distinct from numeric values such as 1234 , although some languages automatically convert between them. A union type definition will specify which of a number of permitted subtypes may be stored in its instances, e.g. "float or long integer". In contrast with a record , which could be defined to contain a float and an integer,

1332-617: A pointer whose value was never a valid memory address would cause a program to crash. To ameliorate this potential problem, a pointer type is typically considered distinct from the corresponding integer type, even if the underlying representation is the same. Functional programming languages treat functions as a distinct datatype and allow values of this type to be stored in variables and passed to functions. Some multi-paradigm languages such as JavaScript also have mechanisms for treating functions as data. Most contemporary type systems go beyond JavaScript's simple type "function object" and have

1406-484: A precision limited only by the available memory and computational resources on the system. Bignum implementations of arithmetic operations on machine-sized values are significantly slower than the corresponding machine operations. The enumerated type has distinct values, which can be compared and assigned, but which do not necessarily have any particular concrete representation in the computer's memory; compilers and interpreters can represent them arbitrarily. For example,

1480-409: A sequence of characters used to store words or plain text , most often textual markup languages representing formatted text . Characters may be a letter of some alphabet , a digit, a blank space, a punctuation mark, etc. Characters are drawn from a character set such as ASCII . Character and string types can have different subtypes according to the character encoding. The original 7-bit wide ASCII

1554-411: A standard format for distributing Python Binaries. Python 3.15 will "Make UTF-8 mode default", the mode exists in all current Python versions, but currently needs to be opted into. UTF-8 is already used, by default, on Windows (and elsewhere), for most things, but e.g. to open files it's not and enabling also makes code fully cross-platform, i.e. use UTF-8 for everything on all platforms. Python

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1628-633: A string literal, with no certainty as to which one a programmer should use. Alex Martelli , a Fellow at the Python Software Foundation and Python book author, wrote: "To describe something as 'clever' is not considered a compliment in the Python culture." Python's developers usually strive to avoid premature optimization and reject patches to non-critical parts of the CPython reference implementation that would offer marginal increases in speed at

1702-421: A type. Product types, function types, power types and list types can be made into type constructors. Universally-quantified and existentially-quantified types are based on predicate logic . Universal quantification is written as ∀ x . f ( x ) {\displaystyle \forall x.f(x)} or forall x. f x and is the intersection over all types x of the body f x , i.e.

1776-413: A union may only contain one subtype at a time. A tagged union (also called a variant , variant record, discriminated union, or disjoint union) contains an additional field indicating its current type for enhanced type safety. An algebraic data type (ADT) is a possibly recursive sum type of product types . A value of an ADT consists of a constructor tag together with zero or more field values, with

1850-415: A word rather as a single bit as it requires more machine instructions to store and retrieve an individual bit. Many programming languages do not have an explicit Boolean type, instead using an integer type and interpreting (for instance) 0 as false and other values as true. Boolean data refers to the logical structure of how the language is interpreted to the machine language. In this case a Boolean 0 refers to

1924-585: Is 1.0 , round(-0.5) is −1.0 . Python allows Boolean expressions with multiple equality relations in a manner that is consistent with general use in mathematics. For example, the expression a < b < c tests whether a is less than b and b is less than c . C-derived languages interpret this expression differently: in C, the expression would first evaluate a < b , resulting in 0 or 1, and that result would then be compared with c . Python uses arbitrary-precision arithmetic for all integer operations. The Decimal type/class in

1998-403: Is floor division. / before version 3.0 is classic division . Rounding towards negative infinity, though different from most languages, adds consistency. For instance, it means that the equation ( a + b ) // b == a // b + 1 is always true. It also means that the equation b * ( a // b ) + a % b == a is valid for both positive and negative values of

2072-1184: Is gp2c , the GP-to-C compiler, which compiles GP scripts into the C language and transparently loads the resulting functions into gp . The advantage of this is that gp2c -compiled scripts will typically run three to four times faster. gp2c understands almost all of GP. PARI/GP performs arbitrary precision calculations (e.g., the significand can be millions of digits long—and billions of digits on 64-bit machines). It can compute factorizations , perform elliptic curve computations and perform algebraic number theory calculations. It also allows computations with matrices , polynomials , power series , algebraic numbers and implements many special functions . PARI/GP comes with its own built-in graphical plotting capability. PARI/GP has some symbolic manipulation capability, e.g., multivariate polynomial and rational function handling. It also has some formal integration and differentiation capabilities. PARI/GP can be compiled with GMP (GNU Multiple Precision Arithmetic Library) providing faster computations than PARI/GP's native arbitrary-precision kernel. PARI/GP's progenitor

2146-522: Is a multi-paradigm programming language . Object-oriented programming and structured programming are fully supported, and many of their features support functional programming and aspect-oriented programming (including metaprogramming and metaobjects ). Many other paradigms are supported via extensions, including design by contract and logic programming . Python is known as a glue language , able to work very well with many other languages with ease of access. Python uses dynamic typing and

2220-544: Is a data type that does not specify the concrete representation of the data. Instead, a formal specification based on the data type's operations is used to describe it. Any implementation of a specification must fulfill the rules given. For example, a stack has push/pop operations that follow a Last-In-First-Out rule, and can be concretely implemented using either a list or an array. Abstract data types are used in formal semantics and program verification and, less strictly, in design . The main non-composite, derived type

2294-488: Is a type whose definition depends on a value. Two common examples of dependent types are dependent functions and dependent pairs. The return type of a dependent function may depend on the value (not just type) of one of its arguments. A dependent pair may have a second value of which the type depends on the first value. An intersection type is a type containing those values that are members of two specified types. For example, in Java

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2368-837: Is also possible to define a dependent intersection type, denoted ( x : σ ) ∩ τ {\displaystyle (x:\sigma )\cap \tau } , where the type τ {\displaystyle \tau } may depend on the term variable x {\displaystyle x} . Some programming languages represent the type information as data, enabling type introspection and reflection . In contrast, higher order type systems , while allowing types to be constructed from other types and passed to functions as values, typically avoid basing computational decisions on them. For convenience, high-level languages and databases may supply ready-made "real world" data types, for instance times, dates, and monetary values (currency). These may be built-in to

2442-492: Is compiled, and possibly semantics are slightly changed. Python's developers aim for it to be fun to use. This is reflected in its name—a tribute to the British comedy group Monty Python —and in occasionally playful approaches to tutorials and reference materials, such as the use of the terms "spam" and "eggs" (a reference to a Monty Python sketch ) in examples, instead of the often-used "foo" and "bar" . A common neologism in

2516-440: Is denoted i32 and panics on overflow in debug mode. Most programming languages also allow the programmer to define additional data types, usually by combining multiple elements of other types and defining the valid operations of the new data type. For example, a programmer might create a new data type named " complex number " that would include real and imaginary parts, or a color data type represented by three bytes denoting

2590-532: Is meant to be an easily readable language. Its formatting is visually uncluttered and often uses English keywords where other languages use punctuation. Unlike many other languages, it does not use curly brackets to delimit blocks, and semicolons after statements are allowed but rarely used. It has fewer syntactic exceptions and special cases than C or Pascal . Python uses whitespace indentation, rather than curly brackets or keywords, to delimit blocks . An increase in indentation comes after certain statements;

2664-411: Is not of a suitable type. Despite being dynamically typed , Python is strongly typed , forbidding operations that are not well-defined (for example, adding a number to a string) rather than silently attempting to make sense of them. Python allows programmers to define their own types using classes , most often used for object-oriented programming . New instances of classes are constructed by calling

2738-502: Is often described as a "batteries included" language due to its comprehensive standard library . Guido van Rossum began working on Python in the late 1980s as a successor to the ABC programming language and first released it in 1991 as Python 0.9.0. Python 2.0 was released in 2000. Python 3.0, released in 2008, was a major revision not completely backward-compatible with earlier versions. Python 2.7.18, released in 2020,

2812-434: Is self-titled "BDFL-emeritus"). In January 2019, active Python core developers elected a five-member Steering Council to lead the project. Python 2.0 was released on 16 October 2000, with many major new features such as list comprehensions , cycle-detecting garbage collection, reference counting , and Unicode support. Python 2.7's end-of-life was initially set for 2015, then postponed to 2020 out of concern that

2886-610: Is slow, inconsistent and buggy [and it has] has many corner cases and oddities. Code that works around those may need to be changed. Code that uses locals() for simple templating, or print debugging, will continue to work correctly." Some (more) standard library modules and many deprecated classes, functions and methods, will be removed in Python 3.15 or 3.16. Python 3.14 is now in alpha 2; regarding possible change to annotations: "In Python 3.14, from __future__ import annotations will continue to work as it did before, converting annotations into strings." PEP 711 proposes PyBI:

2960-543: Is summarized in the Zen of Python (PEP 20), which includes aphorisms such as: However, Python features regularly violate these principles and have received criticism for adding unnecessary language bloat. Responses to these criticisms are that the Zen of Python is a guideline rather than a rule. The addition of some new features had been so controversial that Guido van Rossum resigned as Benevolent Dictator for Life following vitriol over

3034-460: Is that an assignment statement such as a = 1 cannot form part of the conditional expression of a conditional statement. Methods on objects are functions attached to the object's class; the syntax instance . method ( argument ) is, for normal methods and functions, syntactic sugar for Class . method ( instance , argument ) . Python methods have an explicit self parameter to access instance data , in contrast to

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3108-411: Is the pointer , a data type whose value refers directly to (or "points to") another value stored elsewhere in the computer memory using its address . It is a primitive kind of reference . (In everyday terms, a page number in a book could be considered a piece of data that refers to another one). Pointers are often stored in a format similar to an integer; however, attempting to dereference or "look up"

3182-680: Is the oldest supported version of Python (albeit in the 'security support' phase), due to Python 3.8 reaching end-of-life . Starting with 3.13, it and later versions have 2 years of full support (up from one and a half), followed by 3 years of security support (for same total support as before). Security updates were expedited in 2021 (and again twice in 2022, and more fixed in 2023 and in September 2024 for Python 3.12.6 down to 3.8.20), since all Python versions were insecure (including 2.7 ) because of security issues leading to possible remote code execution and web-cache poisoning . Python 3.10 added

3256-548: The decimal module provides decimal floating-point numbers to a pre-defined arbitrary precision and several rounding modes. The Fraction class in the fractions module provides arbitrary precision for rational numbers . Due to Python's extensive mathematics library, and the third-party library NumPy that further extends the native capabilities, it is frequently used as a scientific scripting language to aid in problems such as numerical data processing and manipulation. "Hello, World!" program : Program to calculate

3330-570: The | union type operator and the match and case keywords (for structural pattern matching statements). 3.11 expanded exception handling functionality. Python 3.12 added the new keyword type . Notable changes in 3.11 from 3.10 include increased program execution speed and improved error reporting. Python 3.11 claims to be between 10 and 60% faster than Python 3.10, and Python 3.12 adds another 5% on top of that. It also has improved error messages (again improved in 3.14), and many other changes. Python 3.13 introduces more syntax for types,

3404-571: The Amoeba operating system. Its implementation began in December ;1989. Van Rossum shouldered sole responsibility for the project, as the lead developer, until 12 July 2018, when he announced his "permanent vacation" from his responsibilities as Python's " benevolent dictator for life " (BDFL), a title the Python community bestowed upon him to reflect his long-term commitment as the project's chief decision-maker (he has since come out of retirement and

3478-476: The Python programming language , int represents an arbitrary-precision integer which has the traditional numeric operations such as addition, subtraction, and multiplication. However, in the Java programming language , the type int represents the set of 32-bit integers ranging in value from −2,147,483,648 to 2,147,483,647, with arithmetic operations that wrap on overflow . In Rust this 32-bit integer type

3552-487: The global interpreter lock (GIL), allowing threads to run more concurrently, that latter feature enabled with python3.13t or python3.13t.exe . Python 3.13 introduces some change in behavior, i.e. new "well-defined semantics", fixing bugs (plus many removals of deprecated classes, functions and methods, and removed some of the C ;API and outdated modules): "The [old] implementation of locals() and frame.f_locals

3626-582: The ADT corresponds to a product type similar to a tuple or record. A constructor with no fields corresponds to the empty product (unit type). If all constructors have no fields then the ADT corresponds to an enumerated type . One common ADT is the option type , defined in Haskell as data Maybe a = Nothing | Just a . Some types are very useful for storing and retrieving data and are called data structures . Common data structures include: An abstract data type

3700-403: The Python community is pythonic , which has a wide range of meanings related to program style. "Pythonic" code may use Python idioms well, be natural or show fluency in the language, or conform with Python's minimalist philosophy and emphasis on readability. Code that is difficult to understand or reads like a rough transcription from another programming language is called unpythonic . Python

3774-497: The addition of the assignment expression operator in Python 3.8. Nevertheless, rather than building all of its functionality into its core, Python was designed to be highly extensible via modules. This compact modularity has made it particularly popular as a means of adding programmable interfaces to existing applications. Van Rossum's vision of a small core language with a large standard library and easily extensible interpreter stemmed from his frustrations with ABC , which espoused

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3848-513: The amounts each of red, green, and blue, and a string representing the color's name. Data types are used within type systems , which offer various ways of defining, implementing, and using them. In a type system, a data type represents a constraint placed upon the interpretation of data, describing representation, interpretation and structure of values or objects stored in computer memory. The type system uses data type information to check correctness of computer programs that access or manipulate

3922-544: The authors started to implement a library for "Pascal ARIthmetic" in the Pascal programming language (although they quickly switched to C ), and after "pari de Pascal" ( Pascal's Wager ). The first version of the gp calculator was originally called GPC, for Great Programmable Calculator. The trailing C was eventually dropped. Below are some samples of the gp calculator usage: • PARI/GP online calculator Data type In computer science and computer programming ,

3996-615: The class Boolean implements both the Serializable and the Comparable interfaces. Therefore, an object of type Boolean is a member of the type Serializable & Comparable . Considering types as sets of values, the intersection type σ ∩ τ {\displaystyle \sigma \cap \tau } is the set-theoretic intersection of σ {\displaystyle \sigma } and τ {\displaystyle \tau } . It

4070-475: The class (for example, SpamClass () or EggsClass () ), and the classes are instances of the metaclass type (itself an instance of itself), allowing metaprogramming and reflection . Before version 3.0, Python had two kinds of classes (both using the same syntax): old-style and new-style ; current Python versions only support the semantics of the new style. Python supports optional type annotations . These annotations are not enforced by

4144-399: The cost of clarity. Execution speed can be improved by moving speed-critical functions to extension modules written in languages such as C, or by using a just-in-time compiler like PyPy . It is also possible to cross-compile to other languages , but it either doesn't provide the full speed-up that might be expected, since Python is a very dynamic language , or a restricted subset of Python

4218-614: The data. A compiler may use the static type of a value to optimize the storage it needs and the choice of algorithms for operations on the value. In many C compilers the float data type, for example, is represented in 32 bits , in accord with the IEEE specification for single-precision floating point numbers . They will thus use floating-point-specific microprocessor operations on those values (floating-point addition, multiplication, etc.). Most data types in statistics have comparable types in computer programming, and vice versa, as shown in

4292-474: The following table: Parnas, Shore & Weiss (1976) identified five definitions of a "type" that were used—sometimes implicitly—in the literature: The definition in terms of a representation was often done in imperative languages such as ALGOL and Pascal , while the definition in terms of a value space and behaviour was used in higher-level languages such as Simula and CLU . Types including behavior align more closely with object-oriented models, whereas

4366-410: The form a × 2 (where a and b are integers), but displayed in familiar decimal form. Fixed point data types are convenient for representing monetary values. They are often implemented internally as integers, leading to predefined limits. For independence from architecture details, a Bignum or arbitrary precision numeric type might be supplied. This represents an integer or rational to

4440-422: The four suits in a deck of playing cards may be four enumerators named CLUB , DIAMOND , HEART , SPADE , belonging to an enumerated type named suit . If a variable V is declared having suit as its data type, one can assign any of those four values to it. Some implementations allow programmers to assign integer values to the enumeration values, or even treat them as type-equivalent to integers. Strings are

4514-609: The implicit self (or this ) in some other object-oriented programming languages (e.g., C++ , Java , Objective-C , Ruby ). Python also provides methods, often called dunder methods (due to their names beginning and ending with double-underscores), to allow user-defined classes to modify how they are handled by native operations including length, comparison, in arithmetic operations and type conversion. Python uses duck typing and has typed objects but untyped variable names. Type constraints are not checked at compile time ; rather, operations on an object may fail, signifying that it

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4588-475: The language or implemented as composite types in a library. Python (programming language) Python is a high-level , general-purpose programming language . Its design philosophy emphasizes code readability with the use of significant indentation . Python is dynamically typed and garbage-collected . It supports multiple programming paradigms , including structured (particularly procedural ), object-oriented and functional programming . It

4662-507: The language, but may be used by external tools such as mypy to catch errors. Mypy also supports a Python compiler called mypyc, which leverages type annotations for optimization. 1.33333 Python has the usual symbols for arithmetic operators ( + , - , * , / ), the floor division operator // and the modulo operation % (where the remainder can be negative, e.g. 4 % -3 == -2 ). It also has ** for exponentiation , e.g. 5**3 == 125 and 9**0.5 == 3.0 , and

4736-472: The logic False. True is always a non zero, especially a one which is known as Boolean 1. Almost all programming languages supply one or more integer data types. They may either supply a small number of predefined subtypes restricted to certain ranges (such as short and long and their corresponding unsigned variants in C/C++); or allow users to freely define subranges such as 1..12 (e.g. Pascal / Ada ). If

4810-592: The lowest level. The smallest addressable unit of data is usually a group of bits called a byte (usually an octet , which is 8 bits). The unit processed by machine code instructions is called a word (as of 2011 , typically 32 or 64 bits). Machine data types expose or make available fine-grained control over hardware, but this can also expose implementation details that make code less portable. Hence machine types are mainly used in systems programming or low-level programming languages . In higher-level languages most data types are abstracted in that they do not have

4884-441: The notion of data type, though the possible data types are often restricted by considerations of simplicity, computability, or regularity. An explicit data type declaration typically allows the compiler to choose an efficient machine representation, but the conceptual organization offered by data types should not be discounted. Different languages may use different data types or similar types with different semantics. For example, in

4958-400: The number and type of the field values fixed by the constructor. The set of all possible values of an ADT is the set-theoretic disjoint union (sum), of the sets of all possible values of its variants (product of fields). Values of algebraic types are analyzed with pattern matching, which identifies a value's constructor and extracts the fields it contains. If there is only one constructor, then

5032-458: The opposite approach. Python claims to strive for a simpler, less-cluttered syntax and grammar while giving developers a choice in their coding methodology. In contrast to Perl 's " there is more than one way to do it " motto, Python embraces a "there should be one—and preferably only one—obvious way to do it." philosophy. In practice, however, Python provides many ways to achieve the same task. There are, for example, at least three ways to format

5106-476: The programmer intends to use the data. Most programming languages support basic data types of integer numbers (of varying sizes), floating-point numbers (which approximate real numbers ), characters and Booleans . A data type may be specified for many reasons: similarity, convenience, or to focus the attention. It is frequently a matter of good organization that aids the understanding of complex definitions. Almost all programming languages explicitly include

5180-436: The value is of type f x for every x . Existential quantification written as ∃ x . f ( x ) {\displaystyle \exists x.f(x)} or exists x. f x and is the union over all types x of the body f x , i.e. the value is of type f x for some x . In Haskell, universal quantification is commonly used, but existential types must be encoded by transforming exists a. f

5254-550: Was a program named Isabelle , an interpreter for higher arithmetic , written in 1979 by Henri Cohen and François Dress at the Université Bordeaux 1 . PARI/GP was originally developed in 1985 by a team led by Henri Cohen at Laboratoire A2X and is now maintained by Karim Belabas at the Université Bordeaux 1 with the help of many volunteer contributors. The name PARI is a pun about the project's early stages when

5328-400: Was found to be limited, and superseded by 8, 16 and 32-bit sets, which can encode a wide variety of non-Latin alphabets (such as Hebrew and Chinese ) and other symbols. Strings may be of either variable length or fixed length, and some programming languages have both types. They may also be subtyped by their maximum size. Since most character sets include the digits , it is possible to have

5402-506: Was released on 3 December 2008, with some new semantics and changed syntax. At least every Python release since (now unsupported) 3.5 has added some syntax to the language, and a few later releases have dropped outdated modules, or changed semantics, at least in a minor way. Since 7 October 2024 , Python 3.13 is the latest stable release, and it and, for few more months, 3.12 are the only releases with active support including for bugfixes (as opposed to just for security) and Python 3.9,

5476-506: Was the last release of Python 2. Python consistently ranks as one of the most popular programming languages, and has gained widespread use in the machine learning community. Python was conceived in the late 1980s by Guido van Rossum at Centrum Wiskunde & Informatica (CWI) in the Netherlands as a successor to the ABC programming language, which was inspired by SETL , capable of exception handling and interfacing with

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