On 11/01/23 11:21 am, Jen Kris wrote:
where one object derives from another object (a = b[0], for example), any operation that would alter one will alter the other.
I think you're still confused. In C terms, after a = b[0], a and b[0] are pointers to the same block of memory. If you change that block of memory, then of course you will see the change through either pointer. Here's a rough C translation of some of your Python code: /* mx1 = [ [ 1, 2, 3 ], [ 4, 5, 6 ], [ 7, 8, 9 ] ] */ int **mx1 = (int **)malloc(3 * sizeof(int *)); mx1[0] = (int *)malloc(3 * sizeof(int)); mx1[0][0] = 1; mx1[0][1] = 2; mx1[0][2] = 3; mx1[1] = (int *)malloc(3 * sizeof(int)); mx1[1][0] = 4; mx1[1][1] = 5; mx1[1][2] = 6; mx1[2] = (int *)malloc(3 * sizeof(int)); mx1[2][0] = 7; mx1[2][1] = 8; mx1[2][2] = 9; /* arr1 = mx1[2] */ int *arr1 = mx[2]; /* arr1 = [ 10, 11, 12 ] */ arr1 = (int *)malloc(3 * sizeof(int)); arr1[0] = 10; arr1[1] = 11; arr1[2] = 12; Does that help your understanding? -- Greg -- https://mail.python.org/mailman/listinfo/python-list
