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Kameron
04/22/13 10:14pm

Hi, I've got a question about how Mathematica handles integration of a shifted delta function. For a delta function shifted by a numerical fraction like:

Integrate[DiracDelta[x - 1/2], x]

Mathematica outputs

-1 + HeavisideTheta[-1 + 2 x]

I'm wondering why it taks on the extra -1. Although I understand there should always be an implicit constant of integration anyway, it doesn't make sense to me why mathematica just puts a -1 in the case of shifts by numerical fractions and not in other cases, like:

Integrate[DiracDelta[x - 2], x]
(which gives)
HeavisideTheta[-2 + x]

Or even algebraic fractions:

Integrate[DiracDelta[x - y/2], x]
(which gives)
HeavisideTheta[2 x - y]

Thanks for any ideas or help you can provide!

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Subject (listing for 'Integrating DiracDelta')
Author Date Posted
Integrating DiracDelta Kameron 04/22/13 10:14pm
Re: Integrating DiracDelta jf 04/23/13 11:09am
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