Is there a difference between `board[x, y]` and `board[x][y]` in Python?
That works because the object they are using (in this case numpy array) overloads the __getitem__ method. See this toy example:
class MyArray: def __init__(self, arr): self.arr = arr def __getitem__(self, t): return self.arr[t[0]][t[1]]myarr = MyArray([[1,1,1], [1,2,2], [1,2,2]])print(myarr[0,1])
It does not actually work in base Python (like your example). If you run your code, Python throws an exception: 'TypeError: list indices must be integers or slices, not tuple'.
The 1, 1 passed to board is interpreted as a tuple and since board should be indexed with integers or slices, this won't work.
However, if board were some type of array-like data structure and the developer had implemented support for indexing with tuples, this would work. An example of this is arrays in numpy.