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# numpy.roots

`numpy.``roots`(p)

  Return the roots of a polynomial with coefficients given in p.

  The values in the rank-1 array p are coefficients of a polynomial. If the length of p is n+1 then the polynomial is described by p[0] * x**n + p[1] * x**(n-1) + ... + p[n-1]*x + p[n]

  Parameters : | p : array_like of shape(M,) Rank-1 array of polynomial co-efficients.
  Returns : | out : ndarray An array containing the complex roots of the polynomial.
  Raises : | ValueError: : When p cannot be converted to a rank-1 array.

  See also

  `poly`
    Find the coefficients of a polynomial with a given sequence of roots.
  `polyval`
    Evaluate a polynomial at a point.
  `polyfit`
    Least squares polynomial fit.
  `poly1d`
    A one-dimensional polynomial class.

  Notes

  The algorithm relies on computing the eigenvalues of the companion matrix [R256].

  References

  [R256] | (1, 2) Wikipedia, “Companion matrix”, http://en.wikipedia.org/wiki/Companion_matrix

  Examples

      >>> coeff = [3.2, 2, 1]
      >>> np.roots(coeff)
      array([-0.3125+0.46351241j, -0.3125-0.46351241j])

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