c++ - 无法从 "initializer list"转换

Question

我是新手，遇到 C++ 方面的问题。我正在创建 3D 坐标(x、y 和 z 用于面的每个角，然后是 6 个面)并收到许多错误。这是我的代码:

#include <vector>
int main()
{
    std::vector<int> xyzCoords = {
    { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
    { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
    { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
    { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
    { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
    { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }
    };

    int x1 = 0;
    int y1 = 1;
    int z1 = 2;
    int x2 = 3;
    int y2 = 4;
    int z2 = 5;

    xyzCoords = {
    { x1, y1, z1, x2, y1, z1, x2, y1, z2, x1, y1, z2 },
    { x1, y2, z1, x2, y2, z1, x2, y2, z2, x1, y2, z2 },
    { x1, y2, z1, x1, y1, z1, x1, y1, z2, x1, y2, z2 },
    { x2, y2, z1, x2, y1, z1, x2, y1, z2, x2, y2, z2 },
    { x1, y2, z2, x1, y1, z2, x2, y1, z2, x2, y2, z2 },
    { x1, y2, z1, x1, y1, z1, x2, y1, z1, x2, y2, z1 }
    };
    return 0;
}

这是出现问题的代码。你可以看到我将 xyzCoords 定义为 vector 。我不确定这是否是正确的方法。我也不想单独定义 xyz123。实现这一目标的最佳方法是什么？我应该使用列表、数组还是 vector ？请编写有关如何执行此操作的代码。谢谢! 错误:

E0289: no instance of constructor "std::vector<_Ty, _Alloc>::vector [with _Ty=int, _Alloc=std::allocator]" matches the argument list

E0349: no operator "=" matches these operands

C2440: 'initializing': cannot convert from 'initializer list' to 'std::vector>'

C2679: binary '=': no operator found which takes a right-hand operand of type 'initializer list' (or there is no acceptable conversion)

Answer 1

您的初始化与您声明的类型不匹配。您声明了一个一维数组，而您的初始化是一个二维数组。

std::vector<int> xyzCoords = {
    { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
    { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
    { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
    { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
    { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
    { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }
};

应该是:

std::vector<std::vector<int>> xyzCoords = {
    { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
    { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
    { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
    { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
    { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
    { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }
};

你提到了 xyz 坐标，那你为什么不做一个专门用于坐标的类，例如:

struct Point {
   int x, y, z;
}; 

无论如何，我不建议您使用天真的方法来解决这个问题，因为这将是一个矩阵运算密集型计算。你应该使用 BLAS/LAPACK图书馆或它的包装器，如 Eigen或 Armadillo .他们肯定快得多。