# numpy.polynomial.polynomial.polyadd

polynomial.polynomial.polyadd(c1, c2)

  Add one polynomial to another.

  Returns the sum of two polynomials c1 + c2. The arguments are sequences of coefficients from lowest order term to highest, i.e., [1,2,3] represents the polynomial `1 + 2*x + 3*x**2`.

  Parameters:
    c1, c2 array_like

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

  Returns:
    out ndarray

      The coefficient array representing their sum.

  See also

  `polysub`, `polymulx`, `polymul`, `polydiv`, `polypow`

  Examples

      >>> from numpy.polynomial import polynomial as P
      >>> c1 = (1,2,3)
      >>> c2 = (3,2,1)
      >>> sum = P.polyadd(c1,c2); sum
      array([4.,  4.,  4.])
      >>> P.polyval(2, sum) # 4 + 4(2) + 4(2**2)
      28.0