Talk:Iterated limit

Strange formatting of punctuation

I found the following and several other instances of this same formatting error in this article:

BEGIN QUOTE

For example, let

$f(x,y)={\begin{cases}1&{\text{for }}xy\neq 0\\0&{\text{for }}xy=0\end{cases}}$.

END QUOTE

Is that considered a good way to format the punctuation that ends the sentence? I changed it to the following:

For example, let

$f(x,y)={\begin{cases}1&{\text{for }}xy\neq 0,\\0&{\text{for }}xy=0.\end{cases}}$

Do people look at what they've written after they save it? Michael Hardy (talk) 00:42, 25 June 2026 (UTC)

Exchanging the limits

Someone should rewrite the section on exchanging the order of limits. R. A. Gordon gave an iff test in An iterated limits theorem applied to the Henstock integral, Real Analysis Exchange 21 (1995/96), 774–781, theorem 2. It is stated for "directions" (filter basis). ~2026-47460-44 (talk) 23:55, 31 August 2026 (UTC)