registerfd                package:fda                R Documentation

_R_e_g_i_s_t_e_r _F_u_n_c_t_i_o_n_a_l _D_a_t_a _O_b_j_e_c_t_s

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

     Curves are aligned with a target or template curve using a
     continuous criterion. By aligned is meant that the shape of each
     curve is matched as closely as possible to that of the target by
     means of a smooth increasing transformation of the argument, or a
     warping function.

_U_s_a_g_e:

     registerfd(y0fd, yfd, Wfd0, Lfdobj=2, lambda=1, conv=0.01, iterlim=10,
     dbglev=1, periodic=FALSE, crit=2)

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

   y0fd : A functional data object defining the target. It must be
          univariate and it must define a single functional
          observation. 

    yfd : A functional data object defining the functions to be
          registered to yfd0. 

   Wfd0 : A functional data object defining the initial value of a
          function W(t) that determines the warping function. 

 Lfdobj : Either a nonnegative integer or a linear differential
          operator object that defines a rougness penalty to be applied
          to functional data object Wfd0. If present, the derivative or
          the value of applying the operator is evaluated rather than
          the functions themselves. 

 lambda : A nonnegative smoothing parameter that controls the degree of
          roughness in Wfdobj, and consequently in the monotone
          smoothing function. 

   conv : A criterion for convergence of the iterations. 

iterlim : A limit on the number of iterations. 

 dbglev : Either 0, 1, or 2. This controls the amount information
          printed out on each iteration, with 0 implying no output, 1
          intermediate output level, and 2 full output. 

periodic : A logical variable. If T, the functions are considered to be
          periodic, in which case a constant can be added to all
          argument values after they are warped. 

   crit : An integer that is either 1 or 2 that indicates the nature of
          the continuous registration criterion that is used. If 1, the
          criterion is least squares, and if 2, the criterion is the
          minimum eigenvalue of a cross-product matrix. In general,
          criterion 2 is to be preferred. 

_D_e_t_a_i_l_s:

     The warping function that smoothly and monotonely transforms the
     argument is defined by Wfd0 in the same that the monotone
     smoothing function is for function smooth.monotone. See the help
     file for that function for further details.

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

     A list containing: regstr <- list("regfd"=regfd, "Wfd"=Wfd,
     "shift"=shift)  regfd  The registered versions of the original
     function defined in yfd.  Wfd  The functional data object
     determining the warping functions.  shift  A constant that is
     added to the warped arguments if the data are considered periodic.
     Otherwise, zero.

_N_o_t_e:

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

_R_e_f_e_r_e_n_c_e_s:

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

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

