|
Expression
Expression may refer to: Linguistics * Expression (linguistics), a word, phrase, or sentence * Fixed expression, a form of words with a specific meaning * Idiom, a type of fixed expression * Metaphorical expression, a particular word, phrase, or form of words that has a different meaning than its literal form * Expression (sign language), the expressions and postures of the face and body that contribute to the formation of words when signing Symbolic expression * Expression (architecture), implies a clear and authentic displaying of the character or personality of an individual person * Expression (mathematics), a finite combination of symbols that are well-formed according to applicable rules * Expression (computer science), an instruction to execute something that will return a value * Regular expression, a means of matching strings of text in computing * Expression marks, in music, notating the musical dynamics * Symbolic computation expression * S-expression Bodily expre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Regular Expression
A regular expression (shortened as regex or regexp; sometimes referred to as rational expression) is a sequence of characters that specifies a search pattern in text. Usually such patterns are used by string-searching algorithms for "find" or "find and replace" operations on strings, or for input validation. Regular expression techniques are developed in theoretical computer science and formal language theory. The concept of regular expressions began in the 1950s, when the American mathematician Stephen Cole Kleene formalized the concept of a regular language. They came into common use with Unix text-processing utilities. Different syntaxes for writing regular expressions have existed since the 1980s, one being the POSIX standard and another, widely used, being the Perl syntax. Regular expressions are used in search engines, in search and replace dialogs of word processors and text editors, in text processing utilities such as sed and AWK, and in lexical analysis. Most gener ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gene Expression
Gene expression is the process by which information from a gene is used in the synthesis of a functional gene product that enables it to produce end products, protein or non-coding RNA, and ultimately affect a phenotype, as the final effect. These products are often proteins, but in non-protein-coding genes such as transfer RNA (tRNA) and small nuclear RNA (snRNA), the product is a functional non-coding RNA. Gene expression is summarized in the central dogma of molecular biology first formulated by Francis Crick in 1958, further developed in his 1970 article, and expanded by the subsequent discoveries of reverse transcription and RNA replication. The process of gene expression is used by all known life—eukaryotes (including multicellular organisms), prokaryotes (bacteria and archaea), and utilized by viruses—to generate the macromolecular machinery for life. In genetics, gene expression is the most fundamental level at which the genotype gives rise to the phenotype, '' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Facial Expression
A facial expression is one or more motions or positions of the muscles beneath the skin of the face. According to one set of controversial theories, these movements convey the emotional state of an individual to observers. Facial expressions are a form of nonverbal communication. They are a primary means of conveying social information between humans, but they also occur in most other mammals and some other animal species. (For a discussion of the controversies on these claims, see Fridlund and Russell & Fernandez Dols.) Humans can adopt a facial expression voluntarily or involuntarily, and the neural mechanisms responsible for controlling the expression differ in each case. Voluntary facial expressions are often socially conditioned and follow a cortical route in the brain. Conversely, involuntary facial expressions are believed to be innate and follow a subcortical route in the brain. Facial recognition can be an emotional experience for the brain and the amygdala is highly invo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Emotional Expression
An emotional expression is a behavior that communicates an emotional state or attitude. It can be verbal or nonverbal, and can occur with or without self-awareness. Emotional expressions include facial movements like smiling or scowling, simple behaviors like crying, laughing, or saying "thank you," and more complex behaviors like writing a letter or giving a gift. Individuals have some conscious control of their emotional expressions;Dorset Research & Development Support Unit, 2003"Emotional Expression." Retrieved on: July 23, 2007. however, they need not have conscious awareness of their emotional or affective state in order to express emotion. Researchers in psychology have proposed many different and often competing theoretical models to explain emotions and emotional expression, going as far back as Charles Darwin's discussion of emotion as an evolved capacity. Though there is no universally accepted theory of emotion, theorists in emotion agree that experience of emotions a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
S-expression
In computer programming, an S-expression (or symbolic expression, abbreviated as sexpr or sexp) is an expression in a like-named notation for nested list (tree-structured) data. S-expressions were invented for and popularized by the programming language Lisp, which uses them for source code as well as data. In the usual parenthesized syntax of Lisp, an S-expression is classically definedJohn McCarthy (1960/2006)Recursive functions of symbolic expressions. Originally published in Communications of the ACM. as # an atom of the form ''x'', or # an expression of the form (''x'' . ''y'') where ''x'' and ''y'' are S-expressions. This definition reflects LISP's representation of a list as a series of "cells", each one an ordered pair. In plain lists, ''y'' points to the next cell (if any), thus forming a list. The recursive clause of the definition means that both this representation and the S-expression notation can represent any binary tree. However, the representation can in princi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Expression (mathematics)
In mathematics, an expression or mathematical expression is a finite combination of symbols that is well-formed according to rules that depend on the context. Mathematical symbols can designate numbers ( constants), variables, operations, functions, brackets, punctuation, and grouping to help determine order of operations and other aspects of logical syntax. Many authors distinguish an expression from a '' formula'', the former denoting a mathematical object, and the latter denoting a statement about mathematical objects. For example, 8x-5 is an expression, while 8x-5 \geq 5x-8 is a formula. However, in modern mathematics, and in particular in computer algebra, formulas are viewed as expressions that can be evaluated to ''true'' or ''false'', depending on the values that are given to the variables occurring in the expressions. For example 8x-5 \geq 5x-8 takes the value ''false'' if is given a value less than –1, and the value ''true'' otherwise. Examples The use of e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Symbolic Computation Expression
In mathematics and computer science, computer algebra, also called symbolic computation or algebraic computation, is a scientific area that refers to the study and development of algorithms and software for manipulating mathematical expressions and other mathematical objects. Although computer algebra could be considered a subfield of scientific computing, they are generally considered as distinct fields because scientific computing is usually based on numerical computation with approximate floating point numbers, while symbolic computation emphasizes ''exact'' computation with expressions containing variables that have no given value and are manipulated as symbols. Software applications that perform symbolic calculations are called ''computer algebra systems'', with the term ''system'' alluding to the complexity of the main applications that include, at least, a method to represent mathematical data in a computer, a user programming language (usually different from the language ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microsoft Expression Studio
Microsoft Expression Studio is a discontinued suite of tools for designing and building Web and Windows client applications and rich digital media content. Overview Microsoft introduced Microsoft Expression on September 16, 2005, at Microsoft's Professional Developers Conference 2005 in Los Angeles. Microsoft Expression Encoder was introduced at NAB 2007. Microsoft Expression Studio was released to manufacturing ( RTM) on April 30, 2007. The RTM news was announced at Microsoft's MIX 07 conference for web developers and designers. Microsoft Expression Studio 2 was released on May 1, 2008, which also included a graphical makeover for the suite to an inverse of the previous black-on-white theme. This release brings all products in the suite to version 2, and now also includes Visual Studio Standard 2008. Microsoft Expression Studio is also available to students as downloads via Microsoft's DreamSpark program. Microsoft Expression Studio 3 was released on July 22, 2009. This r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Expression (computer Science)
In computer science, an expression is a syntactic entity in a programming language that may be evaluated to determine its value. It is a combination of one or more constants, variables, functions, and operators that the programming language interprets (according to its particular rules of precedence and of association) and computes to produce ("to return", in a stateful environment) another value. This process, for mathematical expressions, is called ''evaluation''. In simple settings, the resulting value is usually one of various primitive types, such as numerical, string, boolean, complex data type or other types. Expression is often contrasted with statement—a syntactic entity that has no value (an instruction). Examples For example, 2 + 3 is both an arithmetic and programming expression, which evaluates to 5. A variable is an expression because it denotes a value in memory, so y + 6 is also an expression. An example of a relational expression is 4 ≠ 4, which eval ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Self-expression Values
Self-expression values are part of a core value dimension in the modernization process. Self-expression is a cluster of values that include social tolerance, life satisfaction, public expression and an aspiration to liberty. Ronald Inglehart, the University of Michigan professor who developed the theory of post-materialism, has worked extensively with this concept. On the Inglehart–Welzel Cultural Map ''self-expression values'' are contrasted with ''survival values'', illustrating the changes in values across countries and generations. The idea that the world is moving towards self-expression values was discussed at length in an article in the Economist. Self-expression is to say something that you truly believe is important in a form of communication, such as art, speech and dance, or other medium. It is to reveal yourself to others in a way that is special to yourself. Emergence of self-expression values The emergence of the post-industrial society has brought about a wav ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fixed Expression
A phraseme, also called a set phrase, idiomatic phrase, multi-word expression (in computational linguistics), or idiom, is a multi-word or multi-morphemic utterance whose components include at least one that is selectionally constrained or restricted by linguistic convention such that it is not freely chosen. In the most extreme cases, there are expressions such as ''X kicks the bucket'' ≈ ‘person X dies of natural causes, the speaker being flippant about X’s demise’ where the unit is selected as a whole to express a meaning that bears little or no relation to the meanings of its parts. All of the words in this expression are chosen restrictedly, as part of a chunk. At the other extreme, there are collocations such as ''stark naked'', ''hearty laugh'', or ''infinite patience'' where one of the words is chosen freely (''naked'', ''laugh'', and ''patience'', respectively) based on the meaning the speaker wishes to express while the choice of the other (intensifying) word (''st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Idiom
An idiom is a phrase or expression that typically presents a figurative, non-literal meaning attached to the phrase; but some phrases become figurative idioms while retaining the literal meaning of the phrase. Categorized as formulaic language, an idiom's figurative meaning is different from the literal meaning. Idioms occur frequently in all languages; in English alone there are an estimated twenty-five million idiomatic expressions. Derivations Many idiomatic expressions were meant literally in their original use, but sometimes the attribution of the literal meaning changed and the phrase itself grew away from its original roots—typically leading to a folk etymology. For instance, the phrase "spill the beans" (meaning to reveal a secret) is first attested in 1919, but has been said to originate from an ancient method of voting by depositing beans in jars, which could be spilled, prematurely revealing the results. Other idioms are deliberately figurative. For example, "break ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
