|
ABC Software Metric
The ABC software metric was introduced by Jerry Fitzpatrick in 1997 to overcome the drawbacks of the LOC. The metric defines an ABC score as a triplet of values that represent the size of a set of source code statements. An ABC score is calculated by counting the number of assignments (A), number of branches (B), and number of conditionals (C) in a program. ABC score can be applied to individual methods, functions, classes, modules or files within a program. ABC score is represented by a 3-D vector . It can also be represented as a scalar value, which is the magnitude of the vector , and is calculated as follows: ::, , = \surd(A^2 + B^2 + C^2) By convention, an ABC magnitude value is rounded to the nearest tenth. History The concept of measuring software size was first introduced by Maurice Halstead from Purdue University in 1975. He suggested that every computer program consists mainly of tokens: operators and operands. He concluded that a count of the number of uniqu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Source Lines Of Code
Source lines of code (SLOC), also known as lines of code (LOC), is a software metric used to measure the size of a computer program by counting the number of lines in the text of the program's source code. SLOC is typically used to predict the amount of effort that will be required to develop a program, as well as to estimate programming productivity or maintainability once the software is produced. Measurement methods Many useful comparisons involve only the order of magnitude of lines of code in a project. Using lines of code to compare a 10,000-line project to a 100,000-line project is far more useful than when comparing a 20,000-line project with a 21,000-line project. While it is debatable exactly how to measure lines of code, discrepancies of an order of magnitude can be clear indicators of software complexity or man-hours. There are two major types of SLOC measures: physical SLOC (LOC) and logical SLOC (LLOC). Specific definitions of these two measures vary, but the most c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scope (computer Science)
In computer programming, the scope of a name binding (an association of a name to an entity, such as a variable) is the part of a program where the name binding is valid; that is, where the name can be used to refer to the entity. In other parts of the program, the name may refer to a different entity (it may have a different binding), or to nothing at all (it may be unbound). Scope helps prevent name collisions by allowing the same name to refer to different objects – as long as the names have separate scopes. The scope of a name binding is also known as the visibility of an entity, particularly in older or more technical literature—this is from the perspective of the referenced entity, not the referencing name. The term "scope" is also used to refer to the set of ''all'' name bindings that are valid within a part of a program or at a given point in a program, which is more correctly referred to as ''context'' or ''environment''. Strictly speaking and in practice for most pro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Unary Operation
In mathematics, an unary operation is an operation with only one operand, i.e. a single input. This is in contrast to binary operations, which use two operands. An example is any function , where is a set. The function is a unary operation on . Common notations are prefix notation (e.g. ¬, −), postfix notation (e.g. factorial ), functional notation (e.g. or ), and superscripts (e.g. transpose ). Other notations exist as well, for example, in the case of the square root, a horizontal bar extending the square root sign over the argument can indicate the extent of the argument. Examples Unary negative and positive As unary operations have only one operand they are evaluated before other operations containing them. Here is an example using negation: :3 − −2 Here, the first '−' represents the binary subtraction operation, while the second '−' represents the unary negation of the 2 (or '−2' could be taken to mean the integer −2). Therefore, the expression i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Keyword (computer Programming)
Keyword may refer to: Computing * Keyword (Internet search), a word or phrase typically used by bloggers or online content creator to rank a web page on a particular topic * Index term, a term used as a keyword to documents in an information system such as a catalog or a search engine * Keyword advertising, a form of online advertising * Keyword clustering, a search engine optimization technique * A reserved word in a programming language Other * Keyword (linguistics), word which occurs in a text more often than we would expect to occur by chance alone * Keyword (rhetoric) Keywords are the words that academics use to reveal the internal structure of an author's reasoning. While they are used primarily for rhetoric, they are also used in a strictly grammatical sense for structural composition, reasoning, and compre ..., a word that academics use to reveal the internal structure of an author's reasoning * '' Keywords: A Vocabulary of Culture and Society'', 1973 non-fiction book ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conditional Operator
The conditional operator is supported in many programming languages. This term usually refers to ?: as in C, C++, C#, and JavaScript. However, in Java, this term can also refer to && and , , . && and , , In some programming languages, e.g. Java, the term ''conditional operator'' refers to short circuit boolean operators && and , , . The second expression is evaluated only when the first expression is not sufficient to determine the value of the whole expression. Difference from bitwise operator & and , are bitwise operators that occur in many programming languages. The major difference is that bitwise operations operate on the individual bits of a binary numeral, whereas conditional operators operate on logical operations. Additionally, expressions before and after a bitwise operator are always evaluated. if (expression1 , , expression2 , , expression3) If expression 1 is true, expressions 2 and 3 are NOT checked. if (expression1 , expression2 , expression3) This ch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nesting (computing)
In computing science and informatics, nestinghttps://study.com/academy/lesson/nesting-loops-statements-in-c-programming.html, title=Nesting Loops & Statements in C Programming is where information is organized in layers, or where objects contain other similar objects. It almost always refers to self-similar or recursive structures in some sense. Terminology Nesting can mean: * nested calls: ** using several levels of subroutines ** recursive calls * nested levels of parentheses in arithmetic expressions * nested blocks of imperative source code such as nested if-clauses, while-clauses, repeat-until clauses etc. * information hiding: ** nested function definitions with lexical scope ** nested data structures such as records, objects, classes, etc. * nested virtualization, also called recursive virtualization: running a virtual machine inside another virtual machine In spreadsheets In a spreadsheet functions can be ''nested'' one into another, making complex formulas. The func ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Goto
GoTo (goto, GOTO, GO TO or other case combinations, depending on the programming language) is a statement found in many computer programming languages. It performs a one-way transfer of control to another line of code; in contrast a function call normally returns control. The jumped-to locations are usually identified using labels, though some languages use line numbers. At the machine code level, a goto is a form of branch or jump statement, in some cases combined with a stack adjustment. Many languages support the goto statement, and many do not (see § language support). The structured program theorem proved that the goto statement is not necessary to write programs that can be expressed as flow charts; some combination of the three programming constructs of sequence, selection/choice, and repetition/iteration are sufficient for any computation that can be performed by a Turing machine, with the caveat that code duplication and additional variables may need to be introduce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subroutine
In computer programming, a function or subroutine is a sequence of program instructions that performs a specific task, packaged as a unit. This unit can then be used in programs wherever that particular task should be performed. Functions may be defined within programs, or separately in libraries that can be used by many programs. In different programming languages, a function may be called a routine, subprogram, subroutine, method, or procedure. Technically, these terms all have different definitions, and the nomenclature varies from language to language. The generic umbrella term ''callable unit'' is sometimes used. A function is often coded so that it can be started several times and from several places during one execution of the program, including from other functions, and then branch back (''return'') to the next instruction after the ''call'', once the function's task is done. The idea of a subroutine was initially conceived by John Mauchly during his work on ENIAC, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Increment And Decrement Operators
Increment and decrement operators are unary operators that ''add'' or ''subtract'' one, to or from their operand, respectively. They are commonly implemented in imperative programming languages. C-like languages feature two versions (pre- and post-) of each operator with slightly different semantics. In languages syntactically derived from B (including C and its various derivatives), the increment operator is written as ++ and the decrement operator is written as --. Several other languages use inc(x) and dec(x) functions. The increment operator increases, and the decrement operator decreases, the value of its operand by 1. The operand must have an arithmetic or pointer data type, and must refer to a modifiable data object. Pointers values are increased (or decreased) by an amount that makes them point to the next (or previous) element adjacent in memory. In languages that support both versions of the operators: * The ''pre''-increment and ''pre''-decrement operators inc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
C (programming Language)
C (''pronounced like the letter c'') is a General-purpose language, general-purpose computer programming language. It was created in the 1970s by Dennis Ritchie, and remains very widely used and influential. By design, C's features cleanly reflect the capabilities of the targeted CPUs. It has found lasting use in operating systems, device drivers, protocol stacks, though decreasingly for application software. C is commonly used on computer architectures that range from the largest supercomputers to the smallest microcontrollers and embedded systems. A successor to the programming language B (programming language), B, C was originally developed at Bell Labs by Ritchie between 1972 and 1973 to construct utilities running on Unix. It was applied to re-implementing the kernel of the Unix operating system. During the 1980s, C gradually gained popularity. It has become one of the measuring programming language popularity, most widely used programming languages, with C compilers avail ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Semantics (computer Science)
In programming language theory, semantics is the rigorous mathematical study of the meaning of programming languages. Semantics assigns computational meaning to valid strings in a programming language syntax. Semantics describes the processes a computer follows when executing a program in that specific language. This can be shown by describing the relationship between the input and output of a program, or an explanation of how the program will be executed on a certain platform, hence creating a model of computation. History In 1967, Robert W. Floyd publishes the paper ''Assigning meanings to programs''; his chief aim is "a rigorous standard for proofs about computer programs, including proofs of correctness, equivalence, and termination". Floyd further writes: A semantic definition of a programming language, in our approach, is founded on a syntactic definition. It must specify which of the phrases in a syntactically correct program represent commands, and what conditions ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Weighted Sum
A weight function is a mathematical device used when performing a sum, integral, or average to give some elements more "weight" or influence on the result than other elements in the same set. The result of this application of a weight function is a weighted sum or weighted average. Weight functions occur frequently in statistics and analysis, and are closely related to the concept of a measure. Weight functions can be employed in both discrete and continuous settings. They can be used to construct systems of calculus called "weighted calculus" and "meta-calculus".Jane Grossma''Meta-Calculus: Differential and Integral'' , 1981. Discrete weights General definition In the discrete setting, a weight function w \colon A \to \R^+ is a positive function defined on a discrete set A, which is typically finite or countable. The weight function w(a) := 1 corresponds to the ''unweighted'' situation in which all elements have equal weight. One can then apply this weight to various concep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.jpg "Click for more on -> Goto")
