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Does a symbol exist for this operation?

  1. Dec 17, 2011 #1
    (*)_pq = 1 if p> q else 0

    This is kinda like kronecker delta in that its a relational operation. Any clue?
  2. jcsd
  3. Dec 17, 2011 #2
    I think something with characteristic functions would work. Maybe something like

    a_{pq} = \chi_{(q, \infty)}(p)

    \chi_A(x) =
    0 & \text{if} \; \; x \notin A \\
    1 & \text{if} \; \; x \in A \; .
    Does that help? Are p and q real numbers?
  4. Dec 22, 2011 #3


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    Science Advisor
    Gold Member

    the Heaviside step function can also be used for this (just a special case of a characteristic function):

    [itex]u(t)[/itex] is 1 for [itex]t>0[/itex] and 0 for [itex]t<0[/itex].

    Some folks capitalize the U.

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