Talk:Foster's reactance theorem

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File:Reactance anti-LC.svg

Odd that for the formulator of this theorem, a function such as x/(1-x^2) is considered to be increasing (for the range x>0). Won't this lead to difficulties in the application of the theorem to situations where values are being compared? 84.227.254.143 (talk) 10:02, 30 March 2014 (UTC)

:I don't think you can use Foster's theorem in that way (comparing two discrete measurements) to determine if the network is a Foster network or not. Clearly, it will fail if there is a pole between the two measurements. One must have knowledge of the sign of the slope of the function across the whole frequency range. SpinningSpark 13:24, 30 March 2014 (UTC)

::There might be another way to formulate it that won't lead to initial confusion. There's a hint of this in the reference to going clockwise in a Smith diagram -- the monotonicity is really a kind of "around the clock" phase monotonicity, like for tan(x). Not being familiar with the field, I wonder if there is a formulation that draws on the specialist literature, but would also satisfy literalists. Perhaps simply "except when crossing poles"? 84.227.254.143 (talk) 15:54, 30 March 2014 (UTC)

:::The alternative formulation is to say the function always has a positive slope. A function becoming less negative is still increasing. SpinningSpark 17:07, 30 March 2014 (UTC)

{{Talk:Foster's reactance theorem/GA1}}

{{code|It's better to have no short descritption than one that is meaningless}}

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{{ping|Spinningspark}} Hiya! Thanks for reverting my mistake! The short description I added was "A reactance theory of electrical circuits". I was trying to distill the first two sentences of the lead to something most people could understand, or at least recognize the field of science. Can you suggest something simple and accurate? – Reidgreg (talk) 19:25, 1 September 2021 (UTC)

:{{ping|Spinningspark}} Rather than these back-and-forth edits, can we discuss what the short description should be? – Reidgreg (talk) 17:05, 2 September 2021 (UTC)

:: It's a theorem not a theory, it says so right there in the title. I'll stop reverting sds that are misleading or just plain wrong when the sd police stop reverting me for writing ones that are too long, . Sometimes it's just not possible to write an sd that is both accurate and meaningful in less than 40 characters.

:: Having got that off my chest, let's try to be helpful: "An electrical network theorem" works for me. Although since reactance is an electrical engineering term the article title pretty well tells you than much. Almost a case for writing {{Short description|none}} (the template recognises that in case you didn't know). SpinningSpark 18:46, 2 September 2021 (UTC)

:::Ah, I see. I wasn't aware of the earlier conflict with the short description. (The instructions for their purpose and writing them could be clearer.) Also, I feel a bit dense that I didn't bother to check that there was a difference between a theory and a theorem. I won't edit it again unless we can agree on something, and hope that this hasn't caused a muddle with the various article nominations.

:::They don't like A or An, but I'm okay with {{code|Electrical network theorem}} as the short description. I'd thought electrical circuit would be more accessible than electrical network, if they were roughly equivalent, but if the former is not accurate then we certainly shouldn't use it. I guess, as with article title policy, we should go with how those familiar with the subject would define it, rather than generalizing it to the point of inaccuracy. I do think that it's better than no sd. Having 'electrical' there as the first word will do a lot to help uninformed readers understand the general field of the theorem, even if they don't know what an electrical network is. (Not everyone is going to understand 'reactance' without further context.) – Reidgreg (talk) 23:29, 2 September 2021 (UTC)

:My opinion on the situation is to go with the short description without the A/an. I don't have much opinions to state, so this is a short comment. There is a task on the reward board regarding removing these from short descriptions and this just went in my way. Luxtaythe2nd (talk) 18:30, 3 September 2021 (UTC)

::{{ping|Spinningspark}} what do you think, are you okay with Electrical network theorem ? Let me know and I'll set it and fix the wikidata description to match. BTW, I have a better understanding of your frustrations now, seeing the number of edits over the past 48 hours or so. The script makes it easy for people to edit, if not edit responsibly (myself included). – Reidgreg (talk) 18:34, 3 September 2021 (UTC)

::: I'm ok with that. Sometimes the article actually is needed to avoid appearing to say something inaccurate. It's ok in this case, but it really shouldn't be a hard rule. SpinningSpark 19:02, 3 September 2021 (UTC)