PPT里确定三角形外心，即三条边的垂直平分线的交点的VBA代码

要确定三角形外心，可以使用如下VBA代码：Sub FindGravityCenterOfTriangle()
Dim aX As Single, aY As Single, bX As Single, bY As Single, cX As Single, cY As Single
Dim centerX As Single, centerY As SingleaX = InputBox("请输入第一个点X坐标")
aY = InputBox("请输入第一个点Y坐标")
bX = InputBox("请输入第二个点X坐标")
bY = InputBox("请输入第二个点Y坐标")
cX = InputBox("请输入第三个点X坐标")
cY = InputBox("请输入第三个点Y坐标")centerX = (aX + bX + cX) / 3
centerY = (aY + bY + cY) / 3MsgBox "三角形外心的坐标是：(" & centerX & "," & centerY & ")"End Sub

相关问题

三角形外心 c++

三角形外心是三角形三条边的垂直平分线的交点，可以通过求出三角形的垂直平分线交点来得到。假设三角形的三个顶点分别为 A(x1, y1), B(x2, y2), C(x3, y3)，则外心的坐标为：

x = ((y2 - y1) * (y3 - y1) * (y3 - y2) + (x3 * x3 - x1 * x1) * (y2 - y1) + (x2 * x2 - x1 * x1) * (y1 - y3)) / (2 * (x2 - x1) * (y3 - y1) - 2 * (x3 - x1) * (y2 - y1))
y = ((x2 - x1) * (x3 - x1) * (x3 - x2) + (y3 * y3 - y1 * y1) * (x2 - x1) + (y2 * y2 - y1 * y1) * (x1 - x3)) / (2 * (y2 - y1) * (x3 - x1) - 2 * (y3 - y1) * (x2 - x1))

基于c++ 求三维 三角形外心 代码

以下是基于C++的求三维三角形外心的代码：

#include <iostream>
#include <cmath>

using namespace std;

// 三维向量结构体
struct Vector3D {
    double x, y, z;
};

// 三角形结构体
struct Triangle {
    Vector3D vertex[3];
};

// 计算两个向量的叉积
Vector3D crossProduct(Vector3D v1, Vector3D v2) {
    Vector3D result;
    result.x = v1.y * v2.z - v1.z * v2.y;
    result.y = v1.z * v2.x - v1.x * v2.z;
    result.z = v1.x * v2.y - v1.y * v2.x;
    return result;
}

// 计算两个向量的点积
double dotProduct(Vector3D v1, Vector3D v2) {
    return v1.x * v2.x + v1.y * v2.y + v1.z * v2.z;
}

// 计算向量的模长
double magnitude(Vector3D v) {
    return sqrt(v.x * v.x + v.y * v.y + v.z * v.z);
}

// 计算三角形外心
Vector3D circumcenter(Triangle t) {
    Vector3D a = t.vertex[0];
    Vector3D b = t.vertex[1];
    Vector3D c = t.vertex[2];

    Vector3D ab = { b.x - a.x, b.y - a.y, b.z - a.z };
    Vector3D ac = { c.x - a.x, c.y - a.y, c.z - a.z };
    Vector3D bc = { c.x - b.x, c.y - b.y, c.z - b.z };

    double ab2 = dotProduct(ab, ab);
    double ac2 = dotProduct(ac, ac);
    double bc2 = dotProduct(bc, bc);

    Vector3D abXac = crossProduct(ab, ac);
    Vector3D abXbc = crossProduct(ab, bc);
    Vector3D acXbc = crossProduct(ac, bc);

    Vector3D circumcenter = {
        (ab2 * acXbc.x + ac2 * abXbc.x + bc2 * abXac.x) / (2 * magnitude(abXac)),
        (ab2 * acXbc.y + ac2 * abXbc.y + bc2 * abXac.y) / (2 * magnitude(abXac)),
        (ab2 * acXbc.z + ac2 * abXbc.z + bc2 * abXac.z) / (2 * magnitude(abXac))
    };

    circumcenter.x += a.x;
    circumcenter.y += a.y;
    circumcenter.z += a.z;

    return circumcenter;
}

int main() {
    Triangle t;
    cout << "Enter the coordinates of the first vertex: ";
    cin >> t.vertex[0].x >> t.vertex[0].y >> t.vertex[0].z;
    cout << "Enter the coordinates of the second vertex: ";
    cin >> t.vertex[1].x >> t.vertex[1].y >> t.vertex[1].z;
    cout << "Enter the coordinates of the third vertex: ";
    cin >> t.vertex[2].x >> t.vertex[2].y >> t.vertex[2].z;

    Vector3D circumcenter = circumcenter(t);

    cout << "The coordinates of the circumcenter are: ";
    cout << circumcenter.x << " " << circumcenter.y << " " << circumcenter.z << endl;

    return 0;
}

该代码首先定义了三维向量结构体和三角形结构体，并实现了计算两个向量的叉积、点积和模长的函数。然后实现了计算三角形外心的 `circumcenter` 函数，该函数根据公式计算出三角形外心的坐标。最后在 `main` 函数中读入三角形的三个顶点坐标，调用 `circumcenter` 函数计算出外心坐标，最终输出结果。