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What's this function?

  1. Oct 9, 2012 #1
    I have this function representation whch grows exponentially when it reaches X=0, but then it remains constant at some Y

    does anybody know a function which looks like that?

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    Last edited: Oct 9, 2012
  2. jcsd
  3. Oct 9, 2012 #2
    As an example of ##\mathcal C^\infty## but not analytic? As a way to glue ##\mathcal C^\infty##-ly? Such a function is usually explained in Differential Geometry books in a section title Partitions of Unity.
  4. Oct 9, 2012 #3


    Staff: Mentor

    Looks like a logistic function to me. See http://en.wikipedia.org/wiki/Logistic_function.
  5. Oct 9, 2012 #4
    Logistic Function.
  6. Oct 9, 2012 #5


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  7. Oct 9, 2012 #6


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  8. Oct 10, 2012 #7
    Unit step response of a damped harmonic oscillator? (It seems to oscillate a bit at its high point)
  9. Oct 11, 2012 #8
    thank you all very much :biggrin:
  10. Oct 12, 2012 #9

    [itex]y = \frac{1}{1+e^{-x}}[/itex]
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