function [ pc_t, vc_t, tt] = get_free_flight_ball( initial_state,t_max,t_step )
%GET_FREE_FLIGHT_BALL 此处显示有关此函数的摘要
%   此处显示详细说明
if nargin <2
    t_max=3.6e3;
end

if nargin <3
    t_step=1;
end

options=odeset('events',@hit_ground);
tspan = 0:t_step:t_max;
[tt, states] = ode45(@free_flight_state_func, tspan, initial_state, options);
pc_t = states(:,1:3);
vc_t = states(:,4:6);
end