Paraméter

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For usage in computer science and programming, see parameter (computer science).

Citakan:Confusing

Parameter (L: auxiliary measure) nyaeta alesan fungsi matematika nu ayana dianggap kadang-kadang atawa kadua tina diskusi nu pakait. Mangka, naon anu dianggap alesan utama jeung dianggap parameter bisa robah dumasar kana naon anu pakait saterusna.

[édit] Conto

In a section on frequently misused words in his book The Writer's Art, James J. Kilpatrick quoted a letter from a correspondent, giving examples to illustrate the correct use of the word parameter:

W.M. Woods...a mathematician...writes... "...a variable is one of the many things a parameter is not." ... The dependent variable, the speed of the car, depends on the independent variable, the position of the gas pedal.

"[Kilpatrick quoting Woods] Now...the engineers...change the lever arms of the linkage...the speed of the car...will still depend on the pedal position...but in a...different manner. You have changed a parameter"

A parametric equaliser is an audio filter that allows the frequency of maximum cut or boost to be set by one control, and the size of the cut or boost by another. These settings, the frequency level of the peak or trough, are two of the parameters of a frequency response curve, and in a two-control equaliser they completely describe the curve. More elaborate parametric equalisers may allow other parameters to be varied, such as skew. These parameters each describe some aspect of the response curve seen as a whole, over all frequencies. A graphic equaliser provides individual level controls for various frequency bands, each of which acts only on that particular frequency band.

[édit] Tipe parameter

[édit] Matematika

In mathematics, the difference in meaning between a parameter and an argument of a function is that the parameters are the symbols that are part of the function's definition, while arguments are the symbols that are supplied to the function when it is used. The value or objects assigned to the parameters by the corresponding arguments of a function or system are not reassigned during the function's evaluation. So, parameters are effectively constants during the evaluation or processing of that function or system. The value of arguments can change outside of the function and between function usages. This distinction, the parameter's constancy, is a key part of the meaning of a parameter in any situation, often in usage beyond just mathematics.

In some informal situations people regard it as a matter of convention (and therefore a historical accident) whether some or all the arguments of a function are called parameters.

[édit] Elmu komputer

When the terms formal parameter and actual parameter are used, they generally correspond with the definitions used in computer science. In the definition of a function such as

f(x) = x + 2,

x is a formal parameter. When the function is used as in

y = f(3) + 5,

3 is the actual parameter value that is used to solve the equation. These concepts are discussed in a more precise way in functional programming and its foundational disciplines, lambda calculus and combinatory logic.

In computing, the parameters passed to a function subroutine are more normally called arguments.

[édit] Logika

In logic, the parameters passed to (or operated on by) an open predicate are called parameters by some authors (e.g., Prawitz, "Natural Deduction"; Paulson, "Designing a theorem prover"). Parameters locally defined within the predicate are called variables. This extra distinction pays off when defining substitution (without this distinction special provision has to be made to avoid variable capture). Others (maybe most) just call parameters passed to (or operated on by) an open predicate variables, and when defining substitution have to distinguish between free variables and bound variables.

[édit] Rekayasa

In engineering (especially involving data acquisition) the term parameter sometimes loosely refers to an individual measured item. For example an airliner flight data recorder may record 88 different items, each termed a parameter. This usage isn't consistent, as sometimes the term channel refers to an individual measured item, with parameter referring to the setup information about that channel.

[édit] Geometri analisa

Dina geometri, kurva bisa ngagambarkeun sababaraha fungsi. Alesan fungsi taya nu sejen disebut "parameter". Buleudan radius 1 tengahna bisa dituliskeun dina bentuk nu leuwih ti hiji bentuk:

bentuk implicit

x 2 + y 2 = 1

bentuk parameter parametric

(x, y) = (cos t,sin t)

numana t nyaeta parameter.

Hal nu leuwih jentre bisa kapanggih dina persamaan paramétrik.

[édit] Analisa matematika

In mathematical analysis, one often considers "integrals dependent on a parameter". These are of the form

$F(t)=\int_{x_0(t)}^{x_1(t)}f(x;t)\,dx.$

In this formula, t is the argument of the function F on the left-hand side, and the parameter that the integral depends on, on the right-hand side. The quantity x is a dummy variable or variable (or parameter) of integration. Now, if we performed the substitution x=g(y), it would be called a change of variable.

[édit] Teori Probabilitas

In probability theory, one may describe the distribution of a random variable as belonging to a family of probability distributions, distinguished from each other by the values of a finite number of parameters. For example, one talks about "a Poisson distribution with mean value λ", or "a normal distribution with mean μ and variance σ²". The latter formulation and notation leaves some ambiguity whether σ or σ² is the second parameter; the distinction is not always relevant.

It is possible to use the sequence of moments (mean, mean square, ...) or cumulants (mean, variance, ...) as parameters for a probability distribution.

[édit] Statistik

Dina statistics, rarangkay gawe probabilitas diluhur masih keneh dipake, tapi museurkeun kana ngira-ngira parameter sebaran dumasar kana tanpa nu ditempo, atawa tes hipotesis parameterna. Dina estimasi klasik parameter ieu dianggap "angger tapi teu dipikanyaho", tapi dina estimasti Bayes dianggap variabel acak nu sebaranna dianggap tina parameter tadi.

Hal ieu ngamungkinkeun keur make statistik inferen teu make sabagean kulawarga parameter sebaran distribusi. Dina kasus ieu, bisa disebutkeun yen statistik non parameter lawan tina statistik parametrik nu bakal dijelaskeun dina paragrap saterusna. Contona, Spearman salah sahiji tes non-parameter nu diitung tina runtuyan data bari teu merhatikun data nu sabenerna, sabalikna Pearson nyaete tes parameter nu diitung langsung tina data jeung bisa dipake nurunkeun hubungan matematisna.

Statistik nyaeta karakter matematika nu bisa dipake keur ngira-ngira parameter, populasi karakter matematika bisa digambarkeun tina sample nu dicokot. Contona, sample mean ( $\overline X$ ) bisa dipake keur ngira-ngira mean parameter (μ) tina populasi ku cara nyokot sampelna.