catHughes              package:spatstat              R Documentation

_H_u_g_h_e_s' _C_a_t _R_e_t_i_n_a _D_a_t_a

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

     Austin Hughes' data: a point pattern  of ganglion cells in the
     retina of a cat. A marked point pattern.

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

     data(catHughes)

_F_o_r_m_a_t:

     An object of class `"ppp"' representing the point pattern of cell
     locations. Entries include

       `x'      Cartesian x-coordinate of cell
       `y'      Cartesian y-coordinate of cell
       `marks'  factor with levels 0 and 1 indicating ``off'' and ``on'' cells respectively.

     See `ppp.object' for details of the format.

_N_o_t_e_s:

     Austin Hughes' data: a point pattern  of ganglion cells in the
     retina of a cat. 152 ``on'' cells and 142 ``off'' cells in a
     rectangle with dimensions 1.6065 by 1.0 where the unit of
     measurement is approximately 1 mm.

_S_o_u_r_c_e:

     Peter Diggle, personal communication

