C++ qhull二维数据取包络示例代码
时间: 2024-02-28 08:54:54 浏览: 192
qthread示例
下面是使用 qhull 库对二维数据进行凸包计算的示例代码:
```c++
#include <iostream>
#include <vector>
#include <qhull/qhull.h>
using namespace std;
int main()
{
// 构造二维数据
vector<double> points = {0, 0, 0, 1, 1, 1, 1, 0, 0.5, 0.5};
const int numpoints = points.size() / 2;
// 调用 qhull 库进行凸包计算
char flags[] = "qhull s FA";
qhT qh_qhull;
qh_init_A(&qh_qhull);
qh_initflags(flags);
qh_init_B(points.data(), numpoints, 2, false);
qh_qhull();
qh_check_output(&qh_qhull);
qh_triangulate(&qh_qhull);
qh_check_points(&qh_qhull);
// 获取凸包结果
int numfacets = qh_num_facets(&qh_qhull);
facetT *facet = nullptr;
vector<double> hullpoints;
FORALLfacets {
if (!facet->upperdelaunay) {
vertexT *vertex;
FORALLvertices(facet->vertices) {
hullpoints.push_back(vertex->point[0]);
hullpoints.push_back(vertex->point[1]);
}
}
}
// 打印凸包结果
cout << "Convex Hull Points:" << endl;
for (int i = 0; i < hullpoints.size() / 2; i++) {
cout << "(" << hullpoints[i * 2] << ", " << hullpoints[i * 2 + 1] << ")" << endl;
}
// 释放 qhull 库资源
qh_freeqhull(!qh_ALL);
qh_memfreeshort(&qh_qhull, 0);
qh_memfreeshort(&qh_qhull, 1);
return 0;
}
```
上述代码中,我们首先构造了一个包含 5 个点的二维数据,然后调用 qhull 库的接口进行凸包计算。计算完成后,我们遍历凸包结果并打印出来。需要注意的是,在使用 qhull 库时,我们需要手动释放资源以避免内存泄漏。
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