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What does H mean?

  1. Feb 21, 2012 #1
    What does "H" mean?!

    I have this question in my assignment paper:-

    8. Sketch the graph of:
    y = |2x − 2|;
    y = 2H(x − 4)

    (a) is obvious, but how do I sketch (b)? Does "H" stand for some specific constant?
  2. jcsd
  3. Feb 21, 2012 #2
  4. Feb 21, 2012 #3
    Re: What does "H" mean?!

    The webpage in the link you've given says:-
    The function is:-
    0 when x < 0,
    1/2 when x = 0,
    1 when x > 0.
    But here: http://simple.wikipedia.org/wiki/Heaviside_Function, defines the function as:-
    1 when x => 0,
    0 when x < 0.

    To begin with, which should I follow?
  5. Feb 21, 2012 #4
    Re: What does "H" mean?!

    I think that H(0)=0 correponds to an old definition remaining from history and that the standard definition is with H(0)=1/2.
    Generally this is of no consequence in partical applications.
  6. Feb 21, 2012 #5


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    Science Advisor

    Re: What does "H" mean?!

    If one wanted to use an approximation like a fourier series version, then it makes sense to define H(0) as 1/2 based on properties of fourier series when you have this kind of 'Gibbs' phenomenon.
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