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Re: Integrating DiracDelta in Mathematica: how to suppress

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• Subject: [mg128336] Re: Integrating DiracDelta in Mathematica: how to suppress
• From: Alex Krasnov <akrasnov at eecs.berkeley.edu>
• Date: Mon, 8 Oct 2012 02:30:03 -0400 (EDT)
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Look into assumptions. If q2 is in fact real, then you can use the 
following code:

In:	Assuming[Element[q2, Reals], Integrate[DiracDelta[p - q2], {p, -Infinity, Infinity}]]
Out:	1

Alex


On Sun, 7 Oct 2012, Yaj wrote:

> For the integral shown below, how do I get Mathematica to output only the "correct" answer as 1 (for future steps in the notebook) and i.e. have Mathematica NOT OUTPUT the ConditionalExpresssion that q2 is real etc?
>
> In[5]:= Integrate[DiracDelta[p - q2], {p, -Infinity, Infinity}]
>
> Out[5]:= ConditionalExpression[1, q2 \[Element] Reals]
>

• References:
  • Integrating DiracDelta in Mathematica: how to suppress ConditionalExpression
    • From: Yaj <ybhattacharya@gmail.com>