小编zch*_*kui的帖子

According to this Official Documentation:

list[:]

creates a new list by shallow copy. I performed following experiments:

>>> squares = [1, 4, 9, 16, 25]
>>> new_squares = square[:]
>>> squares is new_squares
False
>>> squares[0] is new_squares[0]
True
>>> id(squares)
4468706952
>>> id(new_squares)
4468425032
>>> id(squares[0])
4466081856
>>> id(new_squares[0])
4466081856

All here look good! new_square and square are different object (list here), but because of shallow copy, they share the same content. However, the following results make …

我有关于RNG课程的问题.我想从给定的图像中随机获得不同的点,因此我使用OpenCV文档中推荐的RNG类.代码是:

struct SingleAnt
{
    int row;
    int col;
};
void initializeAnts( SingleAnt *ants, Mat *sourceImage )
{
    RNG rng( 0xFFFFFFFF );
    int imgWidth = sourceImage->cols;
    int imgHight = sourceImage->rows;

    for( int index = 0; index < ANTSNUMBER; index++ ) {
        ants[ index ].col = rng.uniform( 0, imgWidth );
        ants[ index ].row = rng.uniform( 0, imgHight );
    }
}

但是,当我运行此代码时,我每次都得到相同的结果.代码中有错误吗？

大家.

我使用Visual Studio 2013(C++)并在main函数中定义了一个二维数组:

int _tmain(int argc, char **argv) 
{
    int g[3][3] = { { 1, 2, 3, }, { 4, 5, 6, }, { 7, 8, 9, }, };
    ...

    return 0;
}

然后,我在定义1中定义了一个函数:

定义1:

void print_array(int **arr, int kx, int ky)
{
    for (int i = 0; i < kx; i++) {
        for (int j = 0; j < ky; j++) {
            printf("%d ", arr[i][j]);
        }
        printf("\n");
    }
}

我想从main函数调用这个函数:

int _tmain(int argc, char **argv) 
{
    int g[3][3] …