# Talk:Explicit and implicit methods

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## Untitled

Oleg Alexandrov's changes to my last edit improve the article. On two minor points I disagree, and have reverted:

"mathematical" simulation: as distinct from, for example, an electrical LCR circuit to simulate a differential equation.

The "next instance of time" is just wrong; I think you mean "instant". My "interval" is also plain wrong: I was thinking in terms of a delta-T, which it isn't (it's late at night, or maybe I'm just stupid).

Pol098 03:52, 11 March 2006 (UTC) (amended)

Yes, "instant" is best! So we agree. Oleg Alexandrov (talk) 04:03, 11 March 2006 (UTC)
I like your final edit. I think the wording is much better like this. Your article I see; nice one. Pol098 04:12, 11 March 2006 (UTC)

Shouldn't the denominator of equation (4) be 2? --anon

Yes! Fixed, thanks. Oleg Alexandrov (talk) 15:15, 30 June 2006 (UTC)

## Accuracy and CFL condition

I've never used implicit methods, but am aware of their use in avoiding the 'stiffness' of stiff systems. Could someone add to the article a comment on their accuracy regarding by how much one has violated the CFL condition? I'm told that it's something like ${\displaystyle O(\partial t/\lambda _{min})}$, but don't know enough about it to be sure.

...I'm also told that one only ever *uses* implicit methods when you're seeking a final steady state, since you know when you've found the right answer. This is plainly not true, but again, could someone comment on their use in strongly time-dependent systems? 7daysahead (talk) 21:51, 10 July 2010 (UTC)

## No Exact Solution?

I object to the statement "In the vast majority of cases, the equation to be solved when using an implicit scheme is much more complicated than a quadratic equation, and no exact solution exists". In typical cases, an exact solution certainly exists, but there is just not a formula to compute it. The wording of the end of the sentence should to changed as to not be confusing. —Preceding unsigned comment added by 208.120.216.154 (talk) 02:26, 5 October 2010 (UTC)

Indeed, I made some changes now. Nico (talk) 07:49, 8 April 2014 (UTC)

## Assessment comment

The comment(s) below were originally left at Talk:Explicit and implicit methods/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 The comments may be irrelevant or outdated; if so, please feel free to remove this section.

 Pretty decent. Needs more on how to solve the equation for implicit methods, connection with stability, PDE methods. -- Jitse Niesen (talk) 11:46, 28 April 2007 (UTC)

Last edited at 11:46, 28 April 2007 (UTC). Substituted at 14:51, 29 April 2016 (UTC)