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# numpy.polynomial.laguerre.lagmul

`numpy.polynomial.laguerre.``lagmul`(c1, c2)

  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.])