marinus               package:spsurvey               R Documentation

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

     This function converts x,y coordinates measured in units of
     latitude and  longitude, i.e., geographic coordinates measured in
     decimal degrees, to  coordinates in the equidistant, cylindric map
     projection measured in units of kilometers.  The projection center
     is defined as the midpoint in latitude- longitude space.  The map
     projection is here named after Marinus of Tyre.

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

     marinus(lat, lon)

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

     lat: vector of latitudes.

     lon: vector of longitudes.

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

     A matrix with column names "x" and "y" containing the x and y
     coordinates  in the equidistant, cylindric map projection measured
     in units of kilometers.

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

     Denis White White.Denis@epa.gov

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

     J.P. Snyder. USGS Prof. Paper 1395, p. 90.

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

     lat <- 45 + runif(100, -5, 5)
     lon <- 120 + runif(100, -10, 10)
     marinus(lat, lon)

