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]