

_P_i_e_c_e_w_i_s_e _P_o_l_y_n_o_m_i_a_l _S_p_l_i_n_e _R_e_p_r_e_s_e_n_t_a_t_i_o_n

     polySpline(object)
     as.polySpline(object)

_A_r_g_u_m_e_n_t_s:

  object: An object that inherits from class `spline'.

_D_e_s_c_r_i_p_t_i_o_n:

     Create the piecewise polynomial representation of a
     spline object.

_V_a_l_u_e:

     An object that inherits from class `polySpline'.  This
     is the piecewise polynomial representation of a
     univariate spline function.  It is defined by a set of
     distinct numeric values called knots.  The spline func-
     tion is a polynomial function between each successive
     pair of knots.  At each interior knot the polynomial
     segments on each side are constrained to have the same
     value of the function and some of its derivatives.

_A_u_t_h_o_r(_s):

     Douglas Bates and Bill Venables

_S_e_e _A_l_s_o:

     `interpSpline', `periodicSpline', `splineKnots',
     `splineOrder'

_E_x_a_m_p_l_e_s:

     data( women )
     ispl <- polySpline( interpSpline( weight ~ height,  women ) )
     print( ispl )   # print the piecewise polynomial representation
     plot( ispl )    # plots over the range of the knots

