vec2TLmom               package:lmomco               R Documentation

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

     This function converts a vector of trimmed L-moments (TL-moments)
     to a TL-moment object of this package. The object is an R 'list'.
     This function is intended to facilitate the use of TL-moments that
     the user might have from other sources. The first five TL-moments
     are supported (lambda^{(t)}_1, lambda^{(t)}_2, lambda^{(t)}_3, 
     lambda_4, lambda^{(t)}_5, tau^{(t)}, tau^{(t)}_3, tau^{(t)}_4, and
     tau^{(t)}_5).  Because in typical practice, the k >= 3 order
     L-moments are dimensionless ratios  (tau^{(t)}_3, tau^{(t)}_4, and
     tau^{(t)}_5), this function computes lambda^{(t)}_3, 
     lambda^{(t)}_4, lambda^{(t)}_5 from lambda^{(t)}_2 and the ratios.
     However, typical  practice is not set on the use of lambda^{(t)}_2
     or tau^{(t)} as measure of dispersion.  Therefore, this function
     takes an 'lscale' optional logical  ('TRUE|FALSE') argument-if
     lambda^{(t)}_2 is provided and 'lscale=TRUE', then tau is computed
     by the function and if tau is provided, then  lambda^{(t)}_2 is
     computed by the function. The trim level of the TL-moment is
     required.

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

     vec2TLmom(vec,trim,lscale)

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

     vec: A vector of L-moment values in lambda^{(t)}_1, lambda^{(t)}_2
          or tau^{(t)}, tau^{(t)}_3, tau^{(t)}_4, and tau^{(t)}_5
          order.

    trim: The trimming level of the TL-moments (can be zero for the
          ordinary L-moments.)

  lscale: A logical switch on the type of the second value of first
          argument. L-scale (lambda_2) or LCV (tau). Default is 'TRUE',
          the second value in the first argument is lambda_2.

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

     An R 'list' is returned where t represents the 'trim' level.

 lambdas: Vector of the TL-moments. First element is lambda^{(t)}_1,
          second element is lambda^{(t)}_2, and so on.

  ratios: Vector of the L-moment ratios. Second element is  tau^{(t)},
          third element is tau^{(t)}_3 and so on.

    trim: Level of symmetrical trimming used in the computation. 
          Default is 0-the usual L-moments are returned.

  source: An attribute identifying the computational source of the
          L-moments: "TLmoms".

_N_o_t_e:

     It is important to note that the "TL-moment object" returned by
     'TLmoms' is different in structure to that returned by 'TLmoms',
     and similar as the TL-moments should not be confused with the
     ordinary L-moments. Implementation in the package might change. At
     present asymmetrical TL-moment construction using this function is
     not available.s

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

     W.H. Asquith

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

     'lmom.ub', 'TLmoms', 'vec2lmom'

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

     TL <- vec2TLmom(c(12,0.6,0.34,0.20,0.05),lscale=FALSE,trim=1)

