pta                   package:ade4                   R Documentation

_P_a_r_t_i_a_l _T_r_i_a_d_i_c _A_n_a_l_y_s_i_s _o_f _a _K-_t_a_b_l_e_s

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

     performs a partial triadic analysis of a K-tables,  using an
     object of class 'ktab'.

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

     pta(X, scannf = TRUE, nf = 2)
     plot.pta (x, xax = 1, yax = 2, option = 1:4, ...)
     print.pta (x, ...)

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

       X: an object of class 'ktab' where the arrays have 1) the same
          dimensions 2) the same names for columns 3) the same column
          weightings

  scannf: a logical value indicating whether the eigenvalues bar plot
          should be displayed

      nf: if scannf FALSE, an integer indicating the number of kept
          axes

       x: an object of class 'pta'

xax, yax: the numbers of the x-axis and the y-axis

  option: an integer between 1 and 4, otherwise the 4 components of the
          plot are displayed

     ...: further arguments passed to or from other methods

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

     returns a list of class 'pta', sub-class of  'dudi' containing : 

      RV: a matrix with the all RV coefficients

  RV.eig: a numeric vector with the all eigenvalues (interstructure)

  RV.coo: a data frame with the scores of the arrays

tab.names: a vector of characters with the array names

      nf: an integer indicating the number of kept axes

    rank: an integer indicating the rank of the studied matrix

    tabw: a numeric vector with the array weights

      cw: a numeric vector with the column weights

      lw: a numeric vector with the row weights

     eig: a numeric vector with the all eigenvalues (compromis)

    cos2: a numeric vector with the cos between compromise and arrays

     tab: a data frame with the modified array

      li: a data frame with the row coordinates

      l1: a data frame with the row normed scores

      co: a data frame with the column coordinates

      c1: a data frame with the column normed scores

     Tli: a data frame with the row coordinates (each table)

     Tco: a data frame with the column coordinates (each table)

   Tcomp: a data frame with the principal components (each table)

     Tax: a data frame with the principal axes (each table)

      TL: a data frame with the factors for Tli

      TC: a data frame with the factors for Tco

      T4: a data frame with the factors for Tax and Tcomp

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

     P. Bady

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

     Blanc, L., Chessel, D. and Doldec, S. (1998) Etude de la
     stabilit temporelle des structures spatiales par Analyse d'une
     srie de tableaux faunistiques totalement apparis. _Bulletin
     Franais de la Pche et de la Pisciculture_, *348*, 1-21.

      Thioulouse, J., and D. Chessel. 1987. Les analyses multi-tableaux
     en cologie factorielle. I De la typologie d'tat  la typologie
     de fonctionnement par l'analyse triadique. _Acta Oecologica,
     Oecologia Generalis_, *8*, 463-480.

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

     data(meaudret)
     wit1 <- within.pca(meaudret$mil, meaudret$plan$dat, scan = FALSE, 
         scal = "partial")
     kta1 <- ktab.within(wit1, colnames = rep(c("S1","S2","S3","S4","S5"), 4))
     kta2 <- t(kta1)
     pta1 <- pta(kta2, scann = FALSE)
     pta1
     plot(pta1)

