Riemann integrable functions continuous except on a set of measure zero?

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A function is Riemann integrable on a bounded interval if its set of discontinuities has measure zero, but it is not necessarily equal to a continuous function almost everywhere. The example provided illustrates a function that is continuous almost everywhere yet cannot be equal to a continuous function almost everywhere. Despite this, for any ε > 0, a continuous function can be found that matches the original function outside a set of measure less than ε. This highlights the nuanced relationship between Riemann integrability and continuity. Understanding these concepts is crucial for deeper insights into real analysis.
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Is it true that a function is Riemann integrable on a bounded interval only if it's equal to a continuous function almost everywhere? I'd imagine this is the case, given the Riemann-Lebesgue lemma, which says that a function is RI iff its set of discontinuities has measure zero. (So the "continuous function" is then just f restricted to the complement of its set of discontinuities.) But I might be wrong. Help?
 
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I've just discovered this is incorrect. Consider the function

<br /> f(x) = \begin{cases}<br /> 1 &amp; \text{ if } 0\leq x \leq 1/2\\<br /> 0 &amp; \text{ if } 1/2 &lt; x \leq 1<br /> \end{cases}<br />

Then f is continuous almost everywhere, but it cannot be equal to a continuous function almost everywhere by an argument involving inverse images of open sets, etc. Bummer.
 
However, for every e>0, there exists a set A of measure less than e and a continuous function g such that, outside of A, f and g are equal.
 

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