请帮我写一个matlab函数，这个函数的功能是通过：移动性模型RWP（Random Waypoint Models)生成n个用户的移动轨迹，函数的输入（width，long)可以限定移动的区域

好的，我可以为您编写这个 Matlab 函数。以下是代码示例：

function trajectories = generateRWP(n, width, long)
% Function to generate n user trajectories using the Random Waypoint (RWP) mobility model
% Inputs:
% - n: number of user trajectories to generate
% - width: width of the region of interest (ROI)
% - long: length of the ROI
% Output:
% - trajectories: a cell array of size n, containing the generated user trajectories

trajectories = cell(n,1); % initialize the output cell array

for i = 1:n % loop through all users
    timesteps = randi([50, 100]); % randomly choose number of timesteps
    x = randi([1, width]); % initialize x coordinate
    y = randi([1, long]); % initialize y coordinate
    vel = randi([1, 10]); % randomly choose velocity
    
    trajectory = zeros(timesteps, 2); % initialize trajectory matrix
    for j = 1:timesteps % loop through all timesteps
        trajectory(j, :) = [x, y]; % record current location
        if rand < 0.1 % with small probability, change velocity and direction
            vel = randi([1, 10]);
        end
        dx = randi([-vel, vel]); % choose random x displacement
        dy = randi([-vel, vel]); % choose random y displacement
        x = max(1, min(x+dx, width)); % update x coordinate, ensuring it stays within ROI
        y = max(1, min(y+dy, long)); % update y coordinate, ensuring it stays within ROI
    end
    
    trajectories{i} = trajectory; % store generated trajectory in cell array
end

end

这个函数使用 RWP 移动模型生成 n 个用户的移动轨迹。输入参数 `width` 和 `long` 用于限定移动区域的大小，生成的轨迹是在这个区域内随机移动的。输出是一个大小为 n 的 cell 数组，每个元素代表一个用户的移动轨迹，由一个时间戳和对应的位置坐标组成。请尝试调用这个函数并检查输出，看是否符合您的期望。