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Talk:Characteristic function (convex analysis)

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Shouldn't one also adopt the convention $0\cdot \infty=0$?92.227.15.192 (talk) 16:13, 22 April 2015 (UTC)[reply]

In all books of convex analysis this function (taking values $0$ and $\infty$) is called indicator function. 91.32.18.76 (talk) 18:26, 14 October 2015 (UTC)[reply]

Rockafellar 1970 book calls this function the indicator function as do all standard convex analysis books. The characteristic function used in integration is the one taking values 0 or 1. — Preceding unsigned comment added by 206.87.39.202 (talk) 18:37, 26 April 2017 (UTC)[reply]

And clearly, this function is not convex (unless the given set is convex). Boris Tsirelson (talk) 16:31, 19 December 2018 (UTC)[reply]

Characteristic versus indicator

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This article is just confusing. The function in this article is called indicator function in all books on convex analysis, in particular in the cited book by Rockafellar (page 28 of the 1997 edition). (Convex) analysis and probability theory simply use different terminology and this is mixed up in this article ("usual indicator function"). 147.188.251.8 (talk) 21:46, 11 February 2024 (UTC)[reply]