停留热点检测 伪代码
时间: 2023-09-10 07:15:02 浏览: 32
以下是停留热点检测的一个简单伪代码:
```
// 定义停留热点数据结构
struct StayPoint {
double latitude; // 纬度
double longitude; // 经度
int start_time; // 开始时间戳
int end_time; // 结束时间戳
int duration; // 停留时间
};
// 定义轨迹点数据结构
struct TrajectoryPoint {
double latitude; // 纬度
double longitude; // 经度
int timestamp; // 时间戳
};
// 定义停留热点检测函数
vector<StayPoint> detect_staypoints(vector<TrajectoryPoint> trajectory, double distance_threshold, int time_threshold) {
vector<StayPoint> staypoints;
int n = trajectory.size();
int i = 0;
while (i < n) {
int j = i + 1;
while (j < n && trajectory[j].timestamp - trajectory[j-1].timestamp <= time_threshold) {
double distance = compute_distance(trajectory[i], trajectory[j]);
if (distance > distance_threshold) {
int duration = trajectory[j-1].timestamp - trajectory[i].timestamp;
if (duration >= time_threshold) {
StayPoint sp = {trajectory[i].latitude, trajectory[i].longitude, trajectory[i].timestamp, trajectory[j-1].timestamp, duration};
staypoints.push_back(sp);
}
i = j;
break;
}
j++;
}
if (j == n) {
int duration = trajectory[j-1].timestamp - trajectory[i].timestamp;
if (duration >= time_threshold) {
StayPoint sp = {trajectory[i].latitude, trajectory[i].longitude, trajectory[i].timestamp, trajectory[j-1].timestamp, duration};
staypoints.push_back(sp);
}
break;
}
}
return staypoints;
}
```
其中,`compute_distance` 函数用于计算两个轨迹点之间的距离。`distance_threshold` 和 `time_threshold` 分别为距离阈值和时间阈值,用于判断是否进入一个停留热点。函数返回一个包含所有停留热点的向量。