arealSubPolygons         package:hydrosanity         R Documentation

_C_o_m_p_u_t_e _s_u_b-_r_e_g_i_o_n_s _c_l_o_s_e_s_t _t_o _e_a_c_h _p_o_i_n_t

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

     Compute the Voronoi mosaic of a set of points, and intersect it
     with a given polygon. This gives the sub-regions of the polygon
     for which each point is the closest.

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

     arealSubPolygons(x, y = NULL, IDs = row.names(x), boundary, min.area.pct = 0.5)

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

       x: x coordinate of points, or a list containing 'x' and 'y'. 

       y: y coordinate of points. 

     IDs: identification strings for each point. 

boundary: polygon coordinates (coerced to "gpc.poly" class). 

min.area.pct: minimum percentage area of the polygon to be allocated to
          any one site. Sites which would have less area than this will
          be excluded. 

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

     Voronoi mosaic, AKA Thiessen polygons, AKA Dirichlet tesselation.

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

     An object of class 'SpatialPolygons' with ID slots from the
     original 'IDs' argument.

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

     Felix Andrews felix@nfrac.org

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

     'voronoi.mosaic', 'gpc.poly-class', 'SpatialPolygons'

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

     ##---- Should be DIRECTLY executable !! ----
     ##-- ==>  Define data, use random,
     ##--    or do  help(data=index)  for the standard data sets.

