d.geodesic(1)		      Grass User's Manual		 d.geodesic(1)



NNAAMMEE
       dd..ggeeooddeessiicc   -  Displays a geodesic line, tracing the shortest distance
       between two geographic points along a great circle, in a longitude/lat-
       itude data set.
       _(_G_R_A_S_S _D_i_s_p_l_a_y _P_r_o_g_r_a_m_)

SSYYNNOOPPSSIISS
       dd..ggeeooddeessiicc
       dd..ggeeooddeessiicc hheellpp
       dd..ggeeooddeessiicc [ccoooorr==_l_o_n_1_,_l_a_t_1_,_l_o_n_2_,_l_a_t_2] [llccoolloorr==_n_a_m_e] [ttccoolloorr==_n_a_m_e]

DDEESSCCRRIIPPTTIIOONN
       _d_._g_e_o_d_e_s_i_c  displays  a geodesic line in the active frame on the user's
       graphics monitor. This line traces the shortest	distance  between  two
       user-specified  points  on  the	curved surface of a longitude/latitude
       data set.  The two coordinate locations	named  must  fall  within  the
       boundaries of the user's current geographic region.

OOPPTTIIOONNSS
       This  program can be run either interactively or non-interactively.  If
       the user types dd..ggeeooddeessiicc on the command  line  without	other  program
       parameters,  the  mouse will be activated; the user is asked to use the
       mouse to indicate the starting and ending points of each geodesic  line
       to  be  drawn. The default line color (white) and text color (red) will
       be used.


       Alternately, the user can specify the starting and  ending  coordinates
       of  the	geodesic,  line color, and text color on the command line, and
       run the program non-interactively.


       Once the user indicates the starting and ending coordinates of the geo-
       desic,  the  line and its length (in miles) are displayed to the user's
       graphics monitor.



   PPaarraammeetteerrss::
       ccoooorr==_l_o_n_1_,_l_a_t_1_,_l_o_n_2_,_l_a_t_2
	      Starting and ending coordinates, in longitude and latitude  val-
	      ues, of the geodesic line to be drawn.

       llccoolloorr==_n_a_m_e
	      Line color in which geodesic will be displayed.
	      Options: red, orange, yellow, green, blue, magenta, indigo, vio-
	      let, gray, white, black
	      Default: white

       ttccoolloorr==_n_a_m_e
	      Text color in which the length of  the  geodesic	will  be  dis-
	      played.
	      Options: red, orange, yellow, green, blue, magenta, indigo, vio-
	      let, gray, white, black.	Default: red


NNOOTTEESS
       This program works only on GRASS data bases using a  longitude/latitude
       coordinate system.

SSEEEE AALLSSOO
       _d_._r_h_u_m_b_l_i_n_e

AAUUTTHHOORR
       Michael Shapiro, U.S. Army Construction Engineering Research Laboratory

       _L_a_s_t _c_h_a_n_g_e_d_: _$_D_a_t_e_: _2_0_0_2_/_0_1_/_2_5 _0_5_:_4_5_:_3_2 _$



GRASS 5.0							 d.geodesic(1)
