Class ndindex

numpy/lib/index_tricks.py:619–703

An N-dimensional iterator object to index arrays. Given the shape of an array, an `ndindex` instance iterates over the N-dimensional index of the array. At each iteration a tuple of indices is returned, the last dimension is iterated over first. Parameters ---------- s

@set_module('numpy')
class ndindex:
    """
    An N-dimensional iterator object to index arrays.

    Given the shape of an array, an `ndindex` instance iterates over
    the N-dimensional index of the array. At each iteration a tuple
    of indices is returned, the last dimension is iterated over first.

    Parameters
    ----------
    shape : ints, or a single tuple of ints
        The size of each dimension of the array can be passed as
        individual parameters or as the elements of a tuple.

    See Also
    --------
    ndenumerate, flatiter

    Examples
    --------
    Dimensions as individual arguments

    >>> for index in np.ndindex(3, 2, 1):
    ...     print(index)
    (0, 0, 0)
    (0, 1, 0)
    (1, 0, 0)
    (1, 1, 0)
    (2, 0, 0)
    (2, 1, 0)

    Same dimensions - but in a tuple ``(3, 2, 1)``

    >>> for index in np.ndindex((3, 2, 1)):
    ...     print(index)
    (0, 0, 0)
    (0, 1, 0)
    (1, 0, 0)
    (1, 1, 0)
    (2, 0, 0)
    (2, 1, 0)

    """

    def __init__(self, *shape):
        if len(shape) == 1 and isinstance(shape[0], tuple):
            shape = shape[0]
        x = as_strided(_nx.zeros(1), shape=shape,
                       strides=_nx.zeros_like(shape))
        self._it = _nx.nditer(x, flags=['multi_index', 'zerosize_ok'],
                              order='C')

    def __iter__(self):
        return self

    def ndincr(self):
        """
        Increment the multi-dimensional index by one.