Function approximation: Difference between revisions

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A function approximation problem asks us to select a function among a well-defined class that closely matches (approximates) a target function.
A function approximation problem asks us to select a function among a well-defined class that closely matches (approximates) a target function.


There are two major classes of function approximation problems. For known target functions approximation theory investigates how certain known functions can be approximated by a specific class of functions (for example, polynomials or rational functions).
There are two major classes of function approximation problems. For known target functions approximation theory investigates how certain known functions can be approximated by a specific class of functions (for example, polynomials or rational functions).


In the second class of problems, the target function (say ''f'') may be unknown. Instead of an explicit formula, only a set of points of the form (''x'', ''g''(''x'')) is provided.
In the second class of problems, the target function (say ''f'') may be unknown. Instead of an explicit formula, only a set of points of the form (''x'', ''f''(''x'')) is provided. Several techniques for approximating ''f'' may be applicable (depending on the structure of the [[domain]] and [[codomain]] of ''f''), such as [[interpolation]], [[extrapolation]], [[regression analysis]], and [[curve fitting]].
 
 
== See also ==
*[[Approximation theory]]
*[[Least squares approximation]]
*[[Moving least squares]]
*[[Function (mathematics)]]
*[[Regression analysis]][[Category:Suggestion Bot Tag]]

Latest revision as of 11:01, 19 August 2024

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A function approximation problem asks us to select a function among a well-defined class that closely matches (approximates) a target function.

There are two major classes of function approximation problems. For known target functions approximation theory investigates how certain known functions can be approximated by a specific class of functions (for example, polynomials or rational functions).

In the second class of problems, the target function (say f) may be unknown. Instead of an explicit formula, only a set of points of the form (x, f(x)) is provided. Several techniques for approximating f may be applicable (depending on the structure of the domain and codomain of f), such as interpolation, extrapolation, regression analysis, and curve fitting.


See also