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This is documentation for an old release of NumPy (version 1.15). Read this page in the documentation of the latest stable release (version 2.2).

numpy.polynomial.laguerre.lagmul

numpy.polynomial.laguerre.lagmul(c1, c2)[source]

Multiply one Laguerre series by another.

Returns the product of two Laguerre series c1 * c2. The arguments are sequences of coefficients, from lowest order “term” to highest, e.g., [1,2,3] represents the series P_0 + 2*P_1 + 3*P_2.

Parameters:
c1, c2 : array_like

1-D arrays of Laguerre series coefficients ordered from low to high.

Returns:
out : ndarray

Of Laguerre series coefficients representing their product.

See also

lagadd, lagsub, lagdiv, lagpow

Notes

In general, the (polynomial) product of two C-series results in terms that are not in the Laguerre polynomial basis set. Thus, to express the product as a Laguerre series, it is necessary to “reproject” the product onto said basis set, which may produce “unintuitive” (but correct) results; see Examples section below.

Examples

>>>
>>> from numpy.polynomial.laguerre import lagmul
>>> lagmul([1, 2, 3], [0, 1, 2])
array([  8., -13.,  38., -51.,  36.])