+def _add_draw(player1, player2, time)
+ how_long_days = ($options["base-date"] - time)/(3600*24)
+ $players[player1] ||= Hash.new { GSL::Vector[0,0] }
+ $players[player2] ||= Hash.new { GSL::Vector[0,0] }
+ $players[player1][player2] += GSL::Vector[0.5*half_life(how_long_days),0.5*half_life(how_long_days)]
+ $players[player2][player1] += GSL::Vector[0.5*half_life(how_long_days),0.5*half_life(how_long_days)]
+end
+