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# numpy.polysub

`numpy.``polysub`(a1, a2)

  Difference (subtraction) of two polynomials.

  Given two polynomials a1 and a2, returns `a1 - a2`. a1 and a2 can be either array_like sequences of the polynomials’ coefficients (including coefficients equal to zero), or `poly1d` objects.

  Parameters : | a1, a2 : array_like or poly1d Minuend and subtrahend polynomials, respectively.
  Returns : | out : ndarray or poly1d Array or `poly1d` object of the difference polynomial’s coefficients.

  See also

  `polyval`, `polydiv`, `polymul`, `polyadd`

  Examples

      >>> np.polysub([2, 10, -2], [3, 10, -4])
      array([-1,  0,  2])