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Infix Notation
Infix notation is the notation commonly used in arithmetical and logical formulae and statements. It is characterized by the placement of operators between operands—"infixed operators"—such as the plus sign in . Usage Binary relations are often denoted by an infix symbol such as set membership ''a'' ∈ ''A'' when the set ''A'' has ''a'' for an element. In geometry, perpendicular lines ''a'' and ''b'' are denoted a \perp b \ , and in projective geometry two points ''b'' and ''c'' are in perspective when b \ \doublebarwedge \ c while they are connected by a projectivity when b \ \barwedge \ c . Infix notation is more difficult to parse by computers than prefix notation (e.g. + 2 2) or postfix notation (e.g. 2 2 +). However many programming languages use it due to its familiarity. It is more used in arithmetic, e.g. 5 × 6. Further notations Infix notation may also be distinguished from function notation, where the name of a function suggests a particular operation, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Programming Language
A programming language is a system of notation for writing computer programs. Programming languages are described in terms of their Syntax (programming languages), syntax (form) and semantics (computer science), semantics (meaning), usually defined by a formal language. Languages usually provide features such as a type system, Variable (computer science), variables, and mechanisms for Exception handling (programming), error handling. An Programming language implementation, implementation of a programming language is required in order to Execution (computing), execute programs, namely an Interpreter (computing), interpreter or a compiler. An interpreter directly executes the source code, while a compiler produces an executable program. Computer architecture has strongly influenced the design of programming languages, with the most common type (imperative languages—which implement operations in a specified order) developed to perform well on the popular von Neumann architecture. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subject–verb–object Word Order
In linguistic typology, subject–verb–object (SVO) is a sentence structure where the subject comes first, the verb second, and the object third. Languages may be classified according to the dominant sequence of these elements in unmarked sentences (i.e., sentences in which an unusual word order is not used for emphasis). English is included in this group. An example is "Sam ate apples." SVO is the second-most common order by number of known languages, after SOV. Together, SVO and SOV account for more than 87% of the world's languages. The label SVO often includes ergative languages although they do not have nominative subjects. Properties Subject–verb–object languages almost always place relative clauses after the nouns which they modify and adverbial subordinators before the clause modified, with varieties of Chinese being notable exceptions. Although some subject–verb–object languages in West Africa, the best known being Ewe, use postpositions in noun phra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Operator (computer Programming)
In computer programming, an operator is a programming language construct that provides functionality that may not be possible to define as a user-defined function (i.e. sizeof in C) or has syntax different than a function (i.e. infix addition as in a+b). Like other programming language concepts, ''operator'' has a generally accepted, although debatable meaning among practitioners while at the same time each language gives it specific meaning in that context, and therefore the meaning varies by language. Some operators are represented with symbols characters typically not allowed for a function identifier to allow for presentation that is more familiar looking than typical function syntax. For example, a function that tests for greater-than could be named gt, but many languages provide an infix symbolic operator so that code looks more familiar. For example, this: if gt(x, y) then return Can be: if x > y then return Some languages allow a language-defined operator t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shunting Yard Algorithm
In computer science, the shunting yard algorithm is a method for parsing arithmetical or logical expressions, or a combination of both, specified in infix notation. It can produce either a postfix notation string, also known as reverse Polish notation (RPN), or an abstract syntax tree (AST). The algorithm was invented by Edsger Dijkstra, first published in November 1961, and named the "shunting yard" algorithm because its operation resembles that of a railroad shunting yard. Like the evaluation of RPN, the shunting yard algorithm is stack-based. Infix expressions are the form of mathematical notation most people are used to, for instance or . For the conversion there are two text variables ( strings), the input and the output. There is also a stack that holds operators not yet added to the output queue. To convert, the program reads each symbol in order and does something based on that symbol. The result for the above examples would be (in reverse Polish notation) and , resp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polish Notation
Polish notation (PN), also known as normal Polish notation (NPN), Łukasiewicz notation, Warsaw notation, Polish prefix notation, Eastern Notation or simply prefix notation, is a mathematical notation in which Operation (mathematics), operators ''precede'' their operands, in contrast to the more common infix notation, in which operators are placed ''between'' operands, as well as reverse Polish notation (RPN), in which operators ''follow'' their operands. It does not need any parentheses as long as each operator has a fixed arity, number of operands. The description "Polish" refers to the nationality of logician Jan Łukasiewicz, who invented Polish notation in 1924. The term ''Polish notation'' is sometimes taken (as the opposite of ''infix notation'') to also include reverse Polish notation. When Polish notation is used as a syntax for mathematical expressions by programming language Interpreter (computing), interpreters, it is readily parsed into abstract syntax trees and c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reverse Polish Notation
Reverse Polish notation (RPN), also known as reverse Łukasiewicz notation, Polish postfix notation or simply postfix notation, is a mathematical notation in which operators ''follow'' their operands, in contrast to prefix or Polish notation (PN), in which operators ''precede'' their operands. The notation does not need any parentheses for as long as each operator has a fixed number of operands. The term ''postfix notation'' describes the general scheme in mathematics and computer sciences, whereas the term ''reverse Polish notation'' typically refers specifically to the method used to enter calculations into hardware or software calculators, which often have additional side effects and implications depending on the actual implementation involving a stack. The description "Polish" refers to the nationality of logician Jan Łukasiewicz, who invented Polish notation in 1924. The first computer to use postfix notation, though it long remained essentially unknown outside of G ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calculator Input Methods
There are various ways in which calculators interpret keystrokes. These can be categorized into two main types: * On a single-step or immediate-execution calculator, the user presses a key for each operation, calculating all the intermediate results, before the final value is shown. * On an expression or formula calculator, one types in an expression and then presses a key, such as "=" or "Enter", to evaluate the expression. There are various systems for typing in an expression, as described below. Immediate execution The immediate execution mode of operation (also known as single-step, algebraic entry system (AES) or chain calculation mode) is commonly employed on most general-purpose calculators. In most simple four-function calculators, such as the Windows calculator in Standard mode and those included with most early operating systems, each binary operation is executed as soon as the next operator is pressed, and therefore the order of operations in a mathematical expression ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tree Traversal
In computer science, tree traversal (also known as tree search and walking the tree) is a form of graph traversal and refers to the process of visiting (e.g. retrieving, updating, or deleting) each node in a Tree (data structure), tree data structure, exactly once. Such traversals are classified by the order in which the nodes are visited. The following algorithms are described for a binary tree, but they may be generalized to other trees as well. Types Unlike linked lists, one-dimensional arrays and other List of data structures#Linear data structures, linear data structures, which are canonically traversed in linear order, trees may be traversed in multiple ways. They may be traversed in Depth-first search, depth-first or Breadth-first search, breadth-first order. There are three common ways to traverse them in depth-first order: in-order, pre-order and post-order. Beyond these basic traversals, various more complex or hybrid schemes are possible, such as depth-limited searche ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Order Of Operations
In mathematics and computer programming, the order of operations is a collection of rules that reflect conventions about which operations to perform first in order to evaluate a given mathematical expression. These rules are formalized with a ranking of the operations. The rank of an operation is called its precedence, and an operation with a ''higher'' precedence is performed before operations with ''lower'' precedence. Calculators generally perform operations with the same precedence from left to right, but some programming languages and calculators adopt different conventions. For example, multiplication is granted a higher precedence than addition, and it has been this way since the introduction of modern mathematical notation, algebraic notation. Thus, in the expression , the multiplication is performed before addition, and the expression has the value , and not . When exponents were introduced in the 16th and 17th centuries, they were given precedence over both addition ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bracket
A bracket is either of two tall fore- or back-facing punctuation marks commonly used to isolate a segment of text or data from its surroundings. They come in four main pairs of shapes, as given in the box to the right, which also gives their names, that vary between British and American English. "Brackets", without further qualification, are in British English the ... marks and in American English the ... marks. Other symbols are repurposed as brackets in specialist contexts, such as those used by linguists. Brackets are typically deployed in symmetric pairs, and an individual bracket may be identified as a "left" or "right" bracket or, alternatively, an "opening bracket" or "closing bracket", respectively, depending on the directionality of the context. In casual writing and in technical fields such as computing or linguistic analysis of grammar, brackets nest, with segments of bracketed material containing embedded within them other further bracketed sub-segments. The nu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Function Application
In mathematics, function application is the act of applying a function to an argument from its domain so as to obtain the corresponding value from its range. In this sense, function application can be thought of as the opposite of function abstraction. Representation Function application is usually depicted by juxtaposing the variable representing the function with its argument encompassed in parentheses. For example, the following expression represents the application of the function ''ƒ'' to its argument ''x''. :f(x) In some instances, a different notation is used where the parentheses aren't required, and function application can be expressed just by juxtaposition. For example, the following expression can be considered the same as the previous one: :f\; x The latter notation is especially useful in combination with the currying isomorphism. Given a function f : (X \times Y) \to Z, its application is represented as f(x, y) by the former notation and f\;(x,y) (or f \ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
