numpy.polynomial.legendre.legadd

numpy.polynomial.legendre.legadd(c1, c2)

Add one Legendre series to another.

Returns the sum of two Legendre series c1 + c2. The arguments are sequences of coefficients ordered from lowest order term to highest, i.e., [1,2,3] represents the series P_0 + 2*P_1 + 3*P_2.

Parameters:

c1, c2 : array_like

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

Returns:

out : ndarray

Array representing the Legendre series of their sum.

See also

legsub, legmulx, legmul, legdiv, legpow

Notes

Unlike multiplication, division, etc., the sum of two Legendre series is a Legendre series (without having to “reproject” the result onto the basis set) so addition, just like that of “standard” polynomials, is simply “component-wise.”

Examples

>>> from numpy.polynomial import legendre as L
>>> c1 = (1,2,3)
>>> c2 = (3,2,1)
>>> L.legadd(c1,c2)
array([4.,  4.,  4.])