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There is a mix-up regarding ill-posed and ill-conditioned

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Apologies for not making the corrections directly - I'm new here.

In most, if not all, of the places this article uses the term "ill-posed" or "ill posed" (sic), it means ill-conditioned. There's a suitable wikipedia article on "Well-posed problem" to link to and I think it is also used to explain ill-posed.

It is true that x |-> 1/(x-1) is discontinuous at x=1 but the numerical instability of the evaluation is to do with the large gradients close to x=1. Continuity of the square root cannot be given as the explanation for why is it well-condition (if it is well-conditioned).

mikeliuk (talk) 01:13, 18 December 2008 (UTC)[reply]

I found this discussion of "well-posed" and "ill-posed" problematic as well (referring to the examples at the bottom of the sidebar). In particular, the statement that sqrt(x) is well-conditioned because it is continuous is followed by a caveat of "not near 0." It's just as continuous there as anywhere else- is this referring to the fact that the derivative has a greater magnitude near the origin? Does "well-posed" rely on the steepness of the function then? I think the example is better without any caveat. Lily.r.s (talk) 02:37, 30 August 2014 (UTC)[reply]

Thanks for your comment. I tried to improve the examples at the bottom of the sidebar. I'm still not very happy with the explanations, but I find especially 'stability' a tricky word to explain properly based on the sources. -- Jitse Niesen (talk) 14:13, 30 August 2014 (UTC)[reply]

Should be "accurately" instead of "precisely"

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... in "Hedge funds (private investment funds) use tools from all fields of numerical analysis to attempt to calculate the value of stocks and derivatives more precisely than other market participants." ?

English is not my first language, so I don't want to make rash edits regarding... her.193.40.10.181 (talk) 08:23, 5 July 2013 (UTC)[reply]

More footnotes tag

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Hi, I've added a more footnotes tag to the article since it includes a list of references but they are not linked to statements in the article. Regards. Gaba (talk) 16:10, 19 November 2013 (UTC)[reply]

Assessment comment

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The comment(s) below were originally left at Talk:Numerical analysis/Comments, and are posted here for posterity. Following several discussions in past years, these subpages are now deprecated. The comments may be irrelevant or outdated; if so, please feel free to remove this section.

Layout of break-out boxes might need revising to make article apear less cluttered. Consider nominating for Good Article status. Tompw 18:21, 7 October 2006 (UTC)[reply]

Last edited at 22:27, 19 April 2007 (UTC). Substituted at 20:09, 1 May 2016 (UTC)

Text and table in sidebar do not match

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Someone, please help me because the Discretization and numerical integration's text and table doesn't match. Tried to edit but still not sure. I'll revert the changes if I don't find a solution. 05:04, 13 September 2016 — Preceding unsigned comment added by 164.41.4.26 (talk)

The text and table are correct and match. The times given in the table are within the intervals over which velocity is approximated as constant. In fact, the times given are in the center of each interval. Try drawing a sketch to see how the intervals are used to approximate the integral. — Anita5192 (talk) 22:52, 12 September 2016 (UTC)[reply]
I'm sorry, didn't realized that the text was using the numeric integral approximation. Also, sorry for the trouble I caused to you. — Preceding unsigned comment added by 164.41.4.26 (talk) 23:03, 19 September 2016 (UTC)[reply]

Proposed merge of Numerical analyst into Numerical analysis

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No reason for a separate article, and most of the page content is about the history of numerical analysis, not about numerical analysts. Sections listing notable numerical analysts and the relevant prizes could be easily added to the numerical analysis page. Apocheir (talk) 21:21, 30 August 2022 (UTC)[reply]

WP:SILENCE, so I went ahead with the merge. Apocheir (talk) 23:02, 8 September 2022 (UTC)[reply]