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Evaluating an error function

  1. Sep 21, 2015 #1
    Okay so I was integrating an expression and ended up getting an imaginary error function in the answer. I'm not sure where to go from there, I plugged it into wolfram and the root it gave me looks nice but is that worth anything to me?

    The integral was being evaluated from -∞ to ∞, would I need to evaluate the error function from these limits or is the root what I'm looking for?
  2. jcsd
  3. Sep 21, 2015 #2
    Here is the original integral and resulting error function
    9-21-2015 9-40-19 PM.jpg 9-21-2015 9-39-38 PM.jpg
  4. Sep 22, 2015 #3


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    If you want the infinite integral a better approach is to complete the square (in k) of the exponent. net result is I = [itex]e^{\frac{-x^2}{4b}}\sqrt{\frac{\pi}{b}}[/itex].

    Comment: All you are doing is taking the Fourier transform of a normal curve.
  5. Sep 23, 2015 #4
    Okay that makes sense. Thanks!
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