public static bool Check(NewGrid grid, CabMetaData cab)
{
//Console.WriteLine("网格数（单边）："+gridTier);
//Console.WriteLine("网格变长："+gridLength);
//Console.WriteLine("网格边界："+gridXLowBound+" "+gridXUpperBound+" "+gridYLowBound+" "+gridYUpperBound);
//int count = 0;
//foreach (Cell cell in grid.cellList)
//{
// count+=Cell.Check(cell);
//}
//Console.WriteLine(count);
int i = 0, j = 0;
foreach (List <Cell> list in grid.cellList)
{
foreach (Cell cell in list)
{
if (Cell.Check(cell, cab))
{
Console.Write("(" + i + "," + j + ")");
return(true);
}
j++;
}
i++;
}
return(false);
}
//判断是否是核心点
public static List <CabMetaData> IsKeyPoint(NewGrid grid, List <CabMetaData> lst, CabMetaData point)
{
List <CabMetaData> indexList = NewGrid.RangeQuery(grid, point, eps);
if (indexList.Count >= minPts)
{
point.extension = "true";
return(indexList);
}
else
{
return(null);
}
}
/*范围查询：给定查询点和查询范围，返回所有在查询范围中的网格上的点
* 方法：首先，根据查询范围得到要访问的网格上下左右界，使界不超过网格范围
* 然后，遍历在上述界内的所有点，对完全处在查询范围内的单元格，把其中所含的点全部加入结果集；否则，对每个单元格中的点再检查是否在查询范围内
*/
public static List <CabMetaData> RangeQuery(NewGrid grid, CabMetaData queryPoint, double radious)
{
List <CabMetaData> result = new List <CabMetaData>();//结果集
//获取中心点所在单元格
//List<int> index = LocateCell(queryPoint);
//要访问的网格上下左右界
int down, up, left, right;
if (queryPoint.Longitude - radious >= gridXLowBound)
{
left = (int)((queryPoint.Longitude - radious - gridXLowBound) / gridLength);
}
else
{
left = 0;
}
if (queryPoint.Longitude + radious <= gridXUpperBound)
{
right = (int)((queryPoint.Longitude + radious - gridXLowBound) / gridLength);
}
else
{
right = gridTier - 1;
}
if (queryPoint.Latitude - radious >= gridYLowBound)
{
down = (int)((queryPoint.Latitude - radious - gridYLowBound) / gridLength);
}
else
{
down = 0;
}
if (queryPoint.Latitude + radious <= gridYUpperBound)
{
up = (int)((queryPoint.Latitude + radious - gridYLowBound) / gridLength);
}
else
{
up = gridTier - 1;
}
//遍历所有可能在查询范围内的单元格
for (int x = left; x <= right; x++)
{
for (int y = down; y <= up; y++)
{
//对完全处在查询范围内的单元格，把其中所含的点全部加入结果集
if (GetMaxDistBetweenPointAndCell(queryPoint, x, y) <= radious)
{
result.AddRange(grid.cellList[x][y].points);
}
else
{
//对于只有一部分在查询范围内的单元格，对其中的每个点再检查是否在查询范围内
foreach (CabMetaData point in grid.cellList[x][y].points)
{
if (Program.GetDistance(point.Latitude, point.Longitude, queryPoint.Latitude, queryPoint.Longitude) <= radious)
{
result.Add(point);
}
}
}
}
}
return(result);
}
public static double eps = 0.005; //ε半径
//dbscan过程（深度优先方法）
public static List <DBscanCluster> ApplyDbscan(NewGrid grid, List <CabMetaData> pointsList)
{
List <DBscanCluster> resultList = new List <DBscanCluster>();// 存储最后的聚类结果
foreach (CabMetaData point in pointsList)
{
if (!point.extension.Equals(""))
{
continue;
}
else
{
List <CabMetaData> neighboursList = NewGrid.RangeQuery(grid, point, eps);
if (neighboursList.Count >= minPts)
{
point.extension = "core";
resultList.Add(new DBscanCluster());
resultList[resultList.Count - 1].Add(point);
Stack <CabMetaData> neighbourStack = new Stack <CabMetaData>();
foreach (CabMetaData neightbour in neighboursList)
{
if (!neightbour.CabMetaDataId.Equals(point.CabMetaDataId))//没必要把查询点也压入栈中（尽管不影响正确性），减少出栈次数
{
neighbourStack.Push(neightbour);
}
}
while (neighbourStack.Count > 0)
{
CabMetaData currentPoint = neighbourStack.Pop();
if (currentPoint.extension.Equals("") || currentPoint.extension.Equals("noice"))//如果标记为"core"或"neighbour"，说明已经被处理过了
{
resultList[resultList.Count - 1].Add(currentPoint);
if (currentPoint.extension.Equals(""))//如果标记为"noice"，说明肯定不是核心点
{
List <CabMetaData> newNeighboursList = NewGrid.RangeQuery(grid, currentPoint, eps);
if (neighboursList.Count >= minPts)//ε邻域大于密度阈值，标记为"core"
{
currentPoint.extension = "core";
foreach (CabMetaData neightbour in newNeighboursList)
{
if (!neightbour.CabMetaDataId.Equals(currentPoint.CabMetaDataId))//没必要把查询点也压入栈中（尽管不影响正确性），减少出栈次数
{
neighbourStack.Push(neightbour);
}
}
}
else//ε邻域小于密度阈值，标记为"neighbour"
{
currentPoint.extension = "neighbour";
}
}
}
}
}
else
{
point.extension = "noice";
}
}
}
return(resultList);
}
