如何反转一个矩阵的维数(彼此)

Question

我有以下矩阵:

const double values[3][41] = { { -116.99, -116.99, -116.99, -116.99, -116.99,
        -116.99, -116.99, -116.99, -116.99, -116.99, -116.99, -116.99, -116.99,
        -116.99, -116.99, -116.99, -116.99, -116.99, -116.99, -72.385, -60.657,
        -72.385, -116.99, -116.99, -116.99, -116.99, -116.99, -116.99, -116.99,
        -116.99, -116.99, -116.99, -116.99, -116.99, -116.99, -116.99, -116.99,
        -116.99, -116.99, -116.99, -116.99 }, { -116.99, -116.99, -116.99,
        -116.99, -116.99, -116.99, -116.99, -116.99, -116.99, -116.99, -116.99,
        -116.99, -116.99, -116.99, -116.99, -116.99, -116.99, -97.597, -81.568,
        -74.745, -66.323, -74.745, -81.568, -97.597, -116.99, -116.99, -116.99,
        -116.99, -116.99, -116.99, -116.99, -116.99, -116.99, -116.99, -116.99,
        -116.99, -116.99, -116.99, -116.99, -116.99, -116.99 },
        { -116.99, -116.99, -116.99, -116.99, -116.99, -116.99, -116.99,
                -116.99, -116.99, -116.99, -116.99, -116.99, -116.99, -116.99,
                -116.99, -107.26, -97.836, -89.451, -83.642, -78.459, -71.99,
                -78.459, -83.642, -89.451, -97.836, -107.26, -116.99, -116.99,
                -116.99, -116.99, -116.99, -116.99, -116.99, -116.99, -116.99,
                -116.99, -116.99, -116.99, -116.99, -116.99, -116.99 }}

是否有一种快速的方法将其转换为values[3][41]，同时保持值

的正确性?

这些值来自于将输出写入[y][x]而不是[x][y]的设备。我想写一个包装函数从矩阵调用值，但也许有一种方法来反转轴。

Answer 1

你只需要循环一下:

const double values[3][41] = {...};
double newValues[41][3];
for(int i=0; i<3; ++i) {
    for(int j=0; j<41; ++i) {
        newValues[j][i] = values[i][j];
    }
}

但是，这需要两倍的内存空间。也可以在内存中重新排序。