parameter

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parameter

1. one of a number of auxiliary variables in terms of which all the variables in an implicit functional relationship can be explicitly expressed
2. a variable whose behaviour is not being considered and which may for present purposes be regarded as a constant, as y in the partial derivative ∂f(x,y)/∂x

Parameter

 

a variable whose values are used to distinguish elements of a given set. For example, the equation (x — a)2 + (y — b)2 = 1 in rectangular Cartesian coordinates determines the set of all circles of radius 1 in the xOy plane. By setting a = 3 and b = 4, we isolate in this set the completely defined circle with center at (3, 4). Thus, a and b are the parameters of a circle in the set.


Parameter

 

in engineering, a quantity that characterizes a certain aspect of a process, phenomenon, system, or device. Examples of such quantities in mechanical systems are mass, coefficient of friction, moment of inertia, and tension. Such parameters as heat capacity, heat flow, and thermal head are used for thermal processes. Typical electrical parameters are resistance, inductance, and capacitance. The physical processes that occur in a system are describable by equations giving the relation between the variable quantities of the processes. Parameters are usually the coefficients of the equations. They can be constants, or they can be variables dependent on time or the system’s coordinates.

The parameters of a system or device can be lumped or they can be distributed in space relative to one, two, or three coordinates. A typical example of a system with distributed parameters is an electric power transmission line, in which the inductance, capacitance, and resistance (conductance) are distributed along the entire length of the line. An example of a lumped parameter is the load on a small segment of a much longer beam.

M. M. MAIZEL

parameter

[pə′ram·əd·ər]
(crystallography)
Any of the axial lengths or interaxial angles that define a unit cell.
(electricity)
The resistance, capacitance, inductance, or impedance of a circuit element.
The value of a transistor or tube characteristic.
(mathematics)
An arbitrary constant or variable so appearing in a mathematical expression that changing it gives various cases of the phenomenon represented.
(physics)
A quantity which is constant under a given set of conditions, but may be different under other conditions.

parameter

parameter

(1) Any value passed to a program by the user or by another program in order to configure the program for a particular purpose. A parameter may be anything; for example, a file name, a coordinate, a range of values, a money amount or a code of some kind. Parameters may be required as in parameter-driven software (see below) or they may be optional. Parameters are often entered as a series of values following the program name when the program is loaded; for example, a DOS switch defines a parameter. In the command dir /p the /p is a parameter switch that means pause after every screenful.

(2) In programming, a value passed to a subroutine or function for processing. Programming today's graphical applications in languages such as C, C++ and Java requires knowledge of hundreds of parameters.

In the following C function, which creates the text window for the Windows version of this database, there are 11 parameters passed to the CreateWindow routine. Some of them call yet other functions for necessary information. In order to call this routine in a program, the programmer must determine the values for every parameter.

 hWndText = CreateWindow
 (
 "TextWClass",
 NULL,
 WS_CHILD|WS_BORDER|WS_VSCROLL|WS_TABSTOP,
 xChar*23+GetSystemMetrics(SM_CXVSCROLL)+8,
 yChar*4,
 Rect.right-Rect.left+1-xChar*23
    -2*GetSystemMetrics(SM_CXVSCROLL)+5,
 yChar*(Lines+1)+2,
 hWnd,
 IDC_TEXTLIST,
 (HANDLE)hInstance,
 NULL
 );
References in periodicals archive ?
The main task of adaptive control is a prompt regulator parameters adjustment for maintenance of unchangeable (constant) form of output signal in case of object's parameters changing.
The significance of the parameters in the regression models were evaluated by the P values of the regression coefficients corresponding to the parameter.
The RET-He parameter is a sensitive measurement of iron available for red cell production.
The parameter b is equal to zero for the standard vector--axial vector type of weak interactions, and the parameter D is related to time-odd correlations of spin and momenta, therefore in the first Born approximation, it is defined by a time reversal violating process.
Define the minimum and maximum of each variable parameter.
This result indicates the importance of proper selection of laboratory test parameters in order to appropriately mimic each field application.
9]/L in the early phase of infection, acute renal failure with serum creatinine >620 [micro]mol/L is impending, and a tight control of clinical and laboratory parameters, including hospitalization, is mandatory.
Results from three sets of test methods can be plotted together to define a three dimensional domain that can define coating parameters and optimize process requirements.
This new product will greatly assist in optimization because it allows us to extract modeling parameters from measurements of real components to be used for virtual prototyping of systems and subsystems.
In this method the three atoms (NC'O) of the peptide group chromophore are replaced by a single point; parameters for the anisotropic polarizabilities of the chromophores and isotropic polarizabilities of the other atoms are used with atomic coordinates to predict the CD spectrum.
All of the parameters must be identified and weighed as to which are important and where they apply in the decision process.