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Topic: dirac delta function is not a TRUE function??
Replies: 11   Last Post: Jul 19, 2011 11:08 PM

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 Michael Stemper Posts: 671 Registered: 6/26/08
Re: dirac delta function is not a TRUE function??
Posted: Jul 14, 2011 12:22 PM

In article <9f2192a5-9776-4c55-9a2d-eeb93f0559ab@g3g2000prf.googlegroups.com>, MBALOVER <mbalover9@gmail.com> writes:
>On Jul 11, 7:36=A0pm, Gerry Myerson <ge...@maths.mq.edi.ai.i2u4email> wrote:
>> In article <4c1e3a16-63c5-470a-b617-8528f4005...@u6g2000prc.googlegroups.com>, =A0MBALOVER <mbalov...@gmail.com> wrote:

>> > From WIKI, I learn that dirac delta function is not a true function.

>> A function from a set A to a set B is an assignment of
>> an element of B to each element of A.
>>
>> If A and B are not specified, it is often assumed that both
>> are taken to be the set R of real numbers.
>>
>> The Dirac delta function does not assign a real number to zero,
>> and is thus not a true function.

>Thanks Gerry. But I am still confused. I think at x =3D 0, delta(x) =
>infinity.

That's one way of looking at it -- in fact it's the one that I was
taught while studying electical engineering. However, look more
carefully at what was said: "... does not assign a real number to
zero ...".

There is no real number called "infinity".

--
Michael F. Stemper
#include <Standard_Disclaimer>
If you take cranberries and stew them like applesauce,
they taste much more like prunes than rhubarb does.

Date Subject Author
7/11/11 mbalover9@gmail.com
7/11/11 Gerry Myerson
7/12/11 mbalover9@gmail.com
7/12/11 Joshua Cranmer
7/12/11 Tim Little
7/14/11 Michael Stemper
7/14/11 Gerry Myerson
7/18/11 Michael Stemper
7/18/11 Gerry Myerson
7/12/11 Frederick Williams
7/18/11 dan.ms.chaos@gmail.com
7/19/11 jim