variogram              package:spatial              R Documentation

_C_o_m_p_u_t_e _S_p_a_t_i_a_l _V_a_r_i_o_g_r_a_m

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

     Compute spatial (semi-)variogram of spatial data or residuals.

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

     variogram(krig, nint, plotit=TRUE, ...)

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

    krig: trend-surface or kriging object with columns `x', `y', and
          `z' 

    nint: number of bins used 

  plotit: logical for plotting 

     ...: parameters for the plot 

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

     Divides range of data into `nint' bins, and computes the average
     squared difference for pairs with separation in each bin.  Returns
     results for bins with 6 or more pairs.

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

     `x' and `y' coordinates of the variogram and `cnt', the number of
     pairs averaged per bin.

_S_i_d_e _E_f_f_e_c_t_s:

     Plots the variogram if `plotit = TRUE'

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

     `correlogram'

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

     data(topo)
     topo.kr <- surf.ls(2, topo)
     variogram(topo.kr, 25)

