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Aaron Bergman
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It's a standard result that the continuous locus is always G-delta$G_\delta$. For each r>0$r>0$, let U(r)$U(r)$ be the set of points x$x$ such that some neighborhood of x$x$ maps into some ball of radius r$r$. Then each U(r)$U(r)$ is open, and the continuous locus is their intersection. Conversely, given a G-delta$G_\delta$ set, I'm pretty sure it's not hard to construct a function with that continuous locus, though I don't remember how off the top of my head.

It's a standard result that the continuous locus is always G-delta. For each r>0, let U(r) be the set of points x such that some neighborhood of x maps into some ball of radius r. Then each U(r) is open, and the continuous locus is their intersection. Conversely, given a G-delta set, I'm pretty sure it's not hard to construct a function with that continuous locus, though I don't remember how off the top of my head.

It's a standard result that the continuous locus is always $G_\delta$. For each $r>0$, let $U(r)$ be the set of points $x$ such that some neighborhood of $x$ maps into some ball of radius $r$. Then each $U(r)$ is open, and the continuous locus is their intersection. Conversely, given a $G_\delta$ set, I'm pretty sure it's not hard to construct a function with that continuous locus, though I don't remember how off the top of my head.

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Eric Wofsey
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It's a standard result that the continuous locus is always G-delta. For each r>0, let U(r) be the set of points x such that some neighborhood of x maps into some ball of radius r. Then each U(r) is open, and the continuous locus is their intersection. Conversely, given a G-delta set, I'm pretty sure it's not hard to construct a setfunction with that continuous locus, though I don't remember how off the top of my head.

It's a standard result that the continuous locus is always G-delta. For each r>0, let U(r) be the set of points x such that some neighborhood of x maps into some ball of radius r. Then each U(r) is open, and the continuous locus is their intersection. Conversely, given a G-delta set, I'm pretty sure it's not hard to construct a set with that continuous locus, though I don't remember how off the top of my head.

It's a standard result that the continuous locus is always G-delta. For each r>0, let U(r) be the set of points x such that some neighborhood of x maps into some ball of radius r. Then each U(r) is open, and the continuous locus is their intersection. Conversely, given a G-delta set, I'm pretty sure it's not hard to construct a function with that continuous locus, though I don't remember how off the top of my head.

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Eric Wofsey
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It's a standard result that the continuous locus is always G-delta. For each r>0, let U(r) be the set of points x such that some neighborhood of x maps into some ball of radius r. Then each U(r) is open, and the continuous locus is their intersection. Conversely, given a G-delta set, I'm pretty sure it's not hard to construct a set with that continuous locus, though I don't remember how off the top of my head.