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# numpy.polynomial.laguerre.lagmulx

`numpy.polynomial.laguerre.``lagmulx`(c)

  Multiply a Laguerre series by x.

  Multiply the Laguerre series c by x, where x is the independent variable.

  Parameters : | c : array_like 1-D array of Laguerre series coefficients ordered from low to high.
  Returns : | out : ndarray Array representing the result of the multiplication.

  Notes

  The multiplication uses the recursion relationship for Laguerre polynomials in the form

  xP_i(x) = (-(i + 1)*P_{i + 1}(x) + (2i + 1)P_{i}(x) - iP_{i - 1}(x))

  Examples

      >>> from numpy.polynomial.laguerre import lagmulx
      >>> lagmulx([1, 2, 3])
      array([ -1.,  -1.,  11.,  -9.])