polynomial.chebyshev.
chebroots
计算切比雪夫级数的根。
返回多项式的根（也就是“零”）。
System Message: WARNING/2 (P（x）= [i] ＊Ti i（x）。)
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一维系数数组。
序列根的数组。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.polynomial.polyroots
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该值的数列不稳定而产生较大误差。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。
切比雪夫级数的基多项式不是 x 所以这个函数的结果可能看起来是非必然的。
实例
>>> import numpy.polynomial.chebyshev as cheb >>> cheb.chebroots((-1, 1,-1, 1)) # T3 - T2 + T1 - T0 has real roots array([ -5.00000000e-01, 2.60860684e-17, 1.00000000e+00]) # may vary