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Graphic of a point function

  1. Dec 13, 2013 #1
    Hello!

    We know how is a primitive of a any function (file 1), but how will be the graphic of a function like the at file 2 (is a descontinued function, periodic with a unit value in a point interval)?
     

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  2. jcsd
  3. Dec 13, 2013 #2

    Mark44

    Staff: Mentor

    Since your function is nonzero only at a finite or possibly countably infinite number of points, its integral will be zero.
     
  4. Dec 14, 2013 #3
    I found the answer for my question using the geogebra and ploting a simulation of an impulse function and then, integrating and deriving. I found that graphic will be so (file 3).
     

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  5. Dec 14, 2013 #4

    Mark44

    Staff: Mentor

    ???
    Without some more context here, I have no idea what you're doing.
     
  6. Dec 14, 2013 #5
    The ideia was that I wanted to know how plote o graphic of a primitive of a function like the file 2. But, how I'm autodidatic and pass the day studing math, I same already found the answer for my doubt (with much sacrifice, as always). The file 3 shows the primitives of a function (blue) with various impulses.
     
  7. Dec 14, 2013 #6

    Mark44

    Staff: Mentor

    I don't think so, at least not on the basis of what you posted in file2. I think what you're talking about is the Dirac delta function (http://en.wikipedia.org/wiki/Dirac_delta_function).
    Emphasis added by me.
    Your file2 graph seems to me to be three points. If you integrate that, you get zero. If you're talking about unit impulses, which are related to the Dirac delta function, you need to tell us that.
     
  8. Dec 14, 2013 #7
    When I opened this topic, I don't was thinking in delta function, because I didn't understood how it works, so, I was trying to develop other way to arrive at same answer. Now I understood how the delta and heaviside functions works, but not perfectly, because I hoped to able to control the height of a pulse... How I can say if a pulse is bigger than other if all pulses are equal to ∞ !?!? It's no make sense to me.
     
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