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# numpy.polynomial.laguerre.lagfromroots¶

`numpy.polynomial.laguerre.``lagfromroots`(roots)[source]

Generate a Laguerre series with given roots.

The function returns the coefficients of the polynomial

in Laguerre form, where the r_n are the roots specified in roots. If a zero has multiplicity n, then it must appear in roots n times. For instance, if 2 is a root of multiplicity three and 3 is a root of multiplicity 2, then roots looks something like [2, 2, 2, 3, 3]. The roots can appear in any order.

If the returned coefficients are c, then

The coefficient of the last term is not generally 1 for monic polynomials in Laguerre form.

Parameters
rootsarray_like

Sequence containing the roots.

Returns
outndarray

1-D array of coefficients. If all roots are real then out is a real array, if some of the roots are complex, then out is complex even if all the coefficients in the result are real (see Examples below).

`polyfromroots`, `legfromroots`, `chebfromroots`, `hermfromroots`, `hermefromroots`
```>>> from numpy.polynomial.laguerre import lagfromroots, lagval