Purpose

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  This function finds the unique parabola which fits three xy pairs.
  The parabola is given by y = p + q * x + r * x^2

Category

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  utilities

Calling Sequence

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  coeff = parabola(x1, x2, x3, y1, y2, y3, [
                  p = p, q = q, r = r]

Inputs

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  x1: First abscissa
  x2: Second abscissa
  x3: Third abscissa
  y1: First ordinate
  y2: Second ordinate
  y3: Third ordinate

Keyword Parameters

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  p: Set to a variable to hold p
  q: Set to a variable to hold q
  r: Set to a variable to hodl r

Outputs

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  An array [p,q,r] which describes the parabola
  y = p + q * x + r * x^2

Modification History

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  June 2009: Written by Chris Beaumont