SciPy

numpy.polynomial.laguerre.lagmulx

numpy.polynomial.laguerre.lagmulx(c)[source]

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.])