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ParameterThere is little difference in meaning between parameter and argument of a function. It is usually a matter of convention (and therefore a historical accident) whether some or all the arguments of a function are called parameters. The best way to explain this is to illustrate it with examples.
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In analytic geometry, curves are often given as the image of some function. The argument of the function is invariably called "the parameter". A circle of radius 1 centered at the origin can be specified in more than one form:
In mathematical analysis, one often considers "integrals dependent on a parameter". These are of the form
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 Gaussian distribution with mean μ and variance σ2".
In statistics, the probability framework above still holds, but attention shifts to estimating the parameters of a distribution based on observed data, or testing hypotheses about them. In classical estimation[?] these parameters are considered "fixed but unknown", but in Bayesian estimation they are random variables with distributions of their own.
Statistics are mathematical characteristics of samples which are used as estimates of parameters, mathematical characteristics of the populations from which the samples are drawn. For example, the mean (<math>\overline X</math>) of a sample is an estimate of the mean (μ) of the population from which it was drawn.
In programming, the term parameter takes on a specialized meaning. Parameters are a way of allowing the same sequence of commands to operate on different data without re-specifying the instructions.
For example, take the following list of instructions:
In this case, the object that the instructions are to operate on is the parameter. If we give this process a name like Destroy, then referring to Destroy followed by the desired object will perform the actions on that object.
For instance:
Will apply the instructions above to a rock, cake, and car respectively.
Thisn'tion is useful for both being able to reason about a sequence of processes and effectively programming a computer. Much of the theory of programming languages deals with various method of passing parameters. These include: call-by-value, call-by-reference, call-by-name.
To reverence what is ancient, and can plead
That even servitude, the worst of ills,
Is kept and guarded as a sacred thing.
Of rational discussion, that a man.html">man,
Of elements tumultuous, in whom lust
As in the bosoms of the slaves he rules,
Himself the only freeman of his land?
Wage war, with any or with no pretence
And force the beggarly last doit, by means
Of poverty, that thus he may procure
A splendid opportunity to die?
Jotham ascribed to his assembled trees
I' th' shadow of a bramble, and recline
Rejoice in him and celebrate his sway,
Your self-denying zeal that holds it good
His thorns with streamers of continual praise?
The king.html">king who loves the law, respects his bounds.
Freely and with delight, who leaves us free;
We trust him not too far. King though he be,
And vain enough to be ambitious still,
Or covet more than freemen choose to grant:
To administer, to guard, to adorn the state,
To serve him nobly in the common cause
Mark now the difference, ye that boast your love.html">love.html">love.html">love
We love the man; the paltry pageant you:
You the regardless author of its woes:
You chains and bondage for a tyrant's sake.
Our love is principle, and has its root
Yours, a blind instinct, crouches to the rod,
Were kingship as true treasure as it seems,
I would not be a king to be beloved
Where love is more attachment to the throne,
Of a superior, he is never free.
Exposed to manacles, deserves them well.
And forced to abandon what she bravely sought,
And pity for her loss. But that's a cause
Is weakness when opposed; conscious of wrong,
.
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