time				envelope	
period	arrivals departures	ray/coeff
   1	   4	    5		 y 24 - x 18
   2	   6	    4		 y 23 - x 19
   3	   17	    14		ray 23.869696
   4	   32	    32		 y 20 - x 18
   5	   33	    37		 y 23 - x 18
   6	   12	    15		 y 24 - x 17
   7	   10	    14		 y 19 - x 17
   8	   13	    18		 y 25 - x 19
   9	   29	    4		 y 18 - x 23
   10	   22	    5		 y 18 - x 19
   11	   27	    18		ray 22.692248
   12	   14	    31		ray 22.722878
   13	   20	    29		 y 23 - x 17
   14	   9	    12		 y 23 - x 18
   15	   17	    10		 y 20 - x 18
   16	   27	    12		 y 18 - x 19
   17	   22	    17		 y 20 - x 22
   18	   13	    14		ray 23.567711
   19	   29	    33		ray 21.448388
   20	   16	    18		ray 21.719325
   21	   20	    17		 y 23 - x 19
   22	   13	    6		ray 24.051388
   23	   19	    13		ray 21.968125
   24	   28	    16		ray 21.826670
   25	   22	    21		ray 25.585677
   26	   25	    11		ray 25.100886
   27	   19	    18		ray 21.920648
   28	   15	    14		ray 24.998275
   29	   15	    24		ray 25.565071
   30	   11	    16		ray 22.240176
   31	   10	    25		ray 21.790053
   32	   11	    30		ray 21.763600
   33	   15	    21		 y 25 - x 18
   34	   9	    21		 y 24 - x 18
   35	   2	    21		ray 25.812200
