numpy.polynomial.polynomial.polycompanion#

polynomial.polynomial.polycompanion(c)[source]#

Return the companion matrix of c.

The companion matrix for power series cannot be made symmetric by scaling the basis, so this function differs from those for the orthogonal polynomials.

Parameters:

carray_like: 1-D array of polynomial coefficients ordered from low to high degree.

Returns:

matndarray: Companion matrix of dimensions (deg, deg).

Notes

New in version 1.7.0.

Examples

>>> from numpy.polynomial import polynomial as P
>>> c = (1, 2, 3)
>>> P.polycompanion(c)
array([[ 0.        , -0.33333333],
       [ 1.        , -0.66666667]])