polynomial.polynomial.
polyroots
计算多项式的根。
返回多项式的根（也就是“零”）。
System Message: WARNING/2 (P（x）= [i] *X^ I)
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多项式系数的一维数组。
多项式根的数组。如果所有的根都是真实的，那么 out 也是真实的，否则就是复杂的。
参见
numpy.polynomial.chebyshev.chebroots
numpy.polynomial.legendre.legroots
numpy.polynomial.laguerre.lagroots
numpy.polynomial.hermite.hermroots
numpy.polynomial.hermite_e.hermeroots
笔记
根估计作为伴随矩阵的特征值，远离复平面原点的根可能由于幂级数的数值不稳定性而产生较大的误差。重数大于1的根也将显示较大的误差，因为靠近这些点的序列值对根中的误差相对不敏感。在原点附近的孤立根可以通过牛顿方法的几次迭代来改进。
实例
>>> import numpy.polynomial.polynomial as poly >>> poly.polyroots(poly.polyfromroots((-1,0,1))) array([-1., 0., 1.]) >>> poly.polyroots(poly.polyfromroots((-1,0,1))).dtype dtype('float64') >>> j = complex(0,1) >>> poly.polyroots(poly.polyfromroots((-j,0,j))) array([ 0.00000000e+00+0.j, 0.00000000e+00+1.j, 2.77555756e-17-1.j]) # may vary