# Unrestricted algorithm

> Mediated Wiki article. Canonical URL: https://mediated.wiki/source/Unrestricted_algorithm
> Markdown URL: https://mediated.wiki/source/Unrestricted_algorithm.md
> Source: https://en.wikipedia.org/wiki/Unrestricted_algorithm
> Source revision: 1282390521
> License: Creative Commons Attribution-ShareAlike 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/)

An '''unrestricted algorithm''' is an [algorithm](/source/algorithm) for the computation of a [mathematical function](/source/mathematical_function) that puts no restrictions on the range of the [argument](/source/argument_of_a_function) or on the precision that may be demanded in the result.<ref name="Clenshaw">{{cite journal|last1=C.W. Clenshaw and F. W. J. Olver|title=An unrestricted algorithm for the exponential function|journal=SIAM Journal on Numerical Analysis|date=April 1980|volume= 17|issue=2|pages=310–331|jstor=2156615|doi=10.1137/0717026|bibcode=1980SJNA...17..310C }}</ref> The idea of such an algorithm was put forward by C. W. Clenshaw and F. W. J. Olver in a paper published in 1980.<ref name=Clenshaw/><ref name="Brent">{{cite book|last1=Richard P Brent|chapter=Unrestricted algorithms for elementary and special functions|title=Information Processing |volume=80  |editor=S. H. Lavington |publisher=North-Holland, Amsterdam|date=1980|pages=613–619|arxiv=1004.3621}}</ref>

In the problem of developing algorithms for computing, as regards the values of a [real-valued function](/source/real-valued_function) of a [real variable](/source/Function_of_a_real_variable) (e.g., ''g''[''x''] in "restricted" algorithms), the error that can be tolerated in the result is specified in advance. An interval on the [real line](/source/real_line) would also be specified for values when the values of a function are to be evaluated. Different algorithms may have to be applied for evaluating functions outside the interval. An unrestricted algorithm envisages a situation in which a user may stipulate the value of ''x'' and also the precision required in ''g''(''x'') quite arbitrarily. The algorithm should then produce an acceptable result without failure.<ref name = Clenshaw/>

==References==
{{reflist}}

Category:Numerical analysis
*
Category:Theoretical computer science

---
Adapted from the Wikipedia article [Unrestricted algorithm](https://en.wikipedia.org/wiki/Unrestricted_algorithm) by Wikipedia contributors ([contributor history](https://en.wikipedia.org/wiki/Unrestricted_algorithm?action=history)). Available under [Creative Commons Attribution-ShareAlike 4.0 International](https://creativecommons.org/licenses/by-sa/4.0/). Changes may have been made.