numpy.roots¶
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numpy.
roots
(p)[source]¶ 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
Rank-1 array of polynomial coefficients.
Returns: out : ndarray
An array containing the roots of the polynomial.
Raises: ValueError
When p cannot be converted to a rank-1 array.
See also
Notes
The algorithm relies on computing the eigenvalues of the companion matrix [R288].
References
[R288] (1, 2) R. A. Horn & C. R. Johnson, Matrix Analysis. Cambridge, UK: Cambridge University Press, 1999, pp. 146-7. Examples
>>> coeff = [3.2, 2, 1] >>> np.roots(coeff) array([-0.3125+0.46351241j, -0.3125-0.46351241j])