Compute the roots of a Laguerre series.
Return the roots (a.k.a “zeros”) of the Laguerre series represented by cs, which is the sequence of coefficients from lowest order “term” to highest, e.g., [1,2,3] is the series L_0 + 2*L_1 + 3*L_2.
Parameters : | cs : array_like
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Returns : | out : ndarray
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See also
polyroots, chebroots
Notes
Algorithm(s) used:
Remember: because the Laguerre series basis set is different from the “standard” basis set, the results of this function may not be what one is expecting.
Examples
>>> from numpy.polynomial.laguerre import lagroots, lagfromroots
>>> coef = lagfromroots([0, 1, 2])
>>> coef
array([ 2., -8., 12., -6.])
>>> lagroots(coef)
array([ -4.44089210e-16, 1.00000000e+00, 2.00000000e+00])