       Re: Integrating DiracDelta in Mathematica: how to suppress ConditionalExpression

• To: mathgroup at smc.vnet.net
• Subject: [mg128338] Re: Integrating DiracDelta in Mathematica: how to suppress ConditionalExpression
• From: Bob Hanlon <hanlonr357 at gmail.com>
• Date: Mon, 8 Oct 2012 02:30:44 -0400 (EDT)
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```Assuming[Element[q2, Reals],
Integrate[DiracDelta[p - q2],
{p, -Infinity, Infinity}]]

1

Integrate[DiracDelta[p - q2],
{p, -Infinity, Infinity},
Assumptions -> Element[q2, Reals]]

1

Integrate[DiracDelta[p - q2],
{p, -Infinity, Infinity},
GenerateConditions -> False]

1

Simplify[
Integrate[DiracDelta[p - q2],
{p, -Infinity, Infinity}],
Element[q2, Reals]]

1

Bob Hanlon

On Sun, Oct 7, 2012 at 1:32 AM, Yaj <ybhattacharya at gmail.com> 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:= Integrate[DiracDelta[p - q2], {p, -Infinity, Infinity}]
>
> Out:= ConditionalExpression[1, q2 \[Element] Reals]
>

```