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Deriving input-output relationship

  1. Jul 11, 2007 #1
    hi frenz

    i want to how to derive mathematical relation between dependent(output) and independent(input) variables when i know the relation between them at few samples.
    cud someone help me out?
    thanks in advance
  2. jcsd
  3. Jul 11, 2007 #2


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    do you know anything about the functional form? even roughly how it should look? if not then there is no way to extrapolate from a few points to every point.
  4. Jul 11, 2007 #3
    as i told , i know the relation between them at few samples. but i want to generalise as a mathematical relation between them
  5. Jul 11, 2007 #4


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    As olgranpappy says, you can't in general... without at least having a guess to the general form. Given a finite number of samples, you can fit it to a polynomial of sufficiently high degree. However, that polynomial is probably not what you are looking for.

    In addition, note the diagrams in
  6. Jul 12, 2007 #5
    thanks for ur response dear frenz............but let me clear my question again. I have a vector(x) and a vector(y) with the value of x at few points and corresponding value of y. I want to generalize the relation between them with that given samples.
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