Bug in Mathematica's Integrate with PrincipalValue->True

Posted by Janus on Stack Overflow See other posts from Stack Overflow or by Janus
Published on 2010-06-02T06:18:22Z Indexed on 2010/06/02 6:23 UTC
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mathematica

It seems that Mathematica's handling of principal value integrals fails on some corner cases. Consider these two expressions (which should give the same result):

Integrate[UnitBox[x]/(x0 - x), {x, -Infinity, Infinity},
  PrincipalValue -> True, Assumptions -> {x0 > 0}] /. x0 -> 1 // Simplify
Integrate[UnitBox[x]/(x0 - x) /. x0 -> 1, {x, -Infinity, Infinity}, 
  PrincipalValue -> True]

In Mathematica 7.0.0 I get

I Pi+Log[3]
Log[3]

Has this been fixed in later versions? Does anybody have an idea for a (more or less) general workaround?

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Bug in Mathematica's Integrate with PrincipalValue->True - Developer IT

Bug in Mathematica's Integrate with PrincipalValue->True

mathematica

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