| import cupy | |
| from cupy import _core | |
| def column_stack(tup): | |
| """Stacks 1-D and 2-D arrays as columns into a 2-D array. | |
| A 1-D array is first converted to a 2-D column array. Then, the 2-D arrays | |
| are concatenated along the second axis. | |
| Args: | |
| tup (sequence of arrays): 1-D or 2-D arrays to be stacked. | |
| Returns: | |
| cupy.ndarray: A new 2-D array of stacked columns. | |
| .. seealso:: :func:`numpy.column_stack` | |
| """ | |
| if any(not isinstance(a, cupy.ndarray) for a in tup): | |
| raise TypeError('Only cupy arrays can be column stacked') | |
| lst = list(tup) | |
| for i, a in enumerate(lst): | |
| if a.ndim == 1: | |
| a = a[:, cupy.newaxis] | |
| lst[i] = a | |
| elif a.ndim != 2: | |
| raise ValueError( | |
| 'Only 1 or 2 dimensional arrays can be column stacked') | |
| return concatenate(lst, axis=1) | |
| def concatenate(tup, axis=0, out=None, *, dtype=None, casting='same_kind'): | |
| """Joins arrays along an axis. | |
| Args: | |
| tup (sequence of arrays): Arrays to be joined. All of these should have | |
| same dimensionalities except the specified axis. | |
| axis (int or None): The axis to join arrays along. | |
| If axis is None, arrays are flattened before use. | |
| Default is 0. | |
| out (cupy.ndarray): Output array. | |
| dtype (str or dtype): If provided, the destination array will have this | |
| dtype. Cannot be provided together with ``out``. | |
| casting ({‘no’, ‘equiv’, ‘safe’, ‘same_kind’, ‘unsafe’}, optional): | |
| Controls what kind of data casting may occur. Defaults to | |
| ``'same_kind'``. | |
| Returns: | |
| cupy.ndarray: Joined array. | |
| .. seealso:: :func:`numpy.concatenate` | |
| """ | |
| if axis is None: | |
| tup = [m.ravel() for m in tup] | |
| axis = 0 | |
| return _core.concatenate_method(tup, axis, out, dtype, casting) | |
| def dstack(tup): | |
| """Stacks arrays along the third axis. | |
| Args: | |
| tup (sequence of arrays): Arrays to be stacked. Each array is converted | |
| by :func:`cupy.atleast_3d` before stacking. | |
| Returns: | |
| cupy.ndarray: Stacked array. | |
| .. seealso:: :func:`numpy.dstack` | |
| """ | |
| return concatenate([cupy.atleast_3d(m) for m in tup], 2) | |
| def hstack(tup, *, dtype=None, casting='same_kind'): | |
| """Stacks arrays horizontally. | |
| If an input array has one dimension, then the array is treated as a | |
| horizontal vector and stacked along the first axis. Otherwise, the array is | |
| stacked along the second axis. | |
| Args: | |
| tup (sequence of arrays): Arrays to be stacked. | |
| dtype (str or dtype): If provided, the destination array will have this | |
| dtype. | |
| casting ({‘no’, ‘equiv’, ‘safe’, ‘same_kind’, ‘unsafe’}, optional): | |
| Controls what kind of data casting may occur. Defaults to | |
| ``'same_kind'``. | |
| Returns: | |
| cupy.ndarray: Stacked array. | |
| .. seealso:: :func:`numpy.hstack` | |
| """ | |
| arrs = [cupy.atleast_1d(a) for a in tup] | |
| axis = 1 | |
| if arrs[0].ndim == 1: | |
| axis = 0 | |
| return concatenate(arrs, axis, dtype=dtype, casting=casting) | |
| def vstack(tup, *, dtype=None, casting='same_kind'): | |
| """Stacks arrays vertically. | |
| If an input array has one dimension, then the array is treated as a | |
| horizontal vector and stacked along the additional axis at the head. | |
| Otherwise, the array is stacked along the first axis. | |
| Args: | |
| tup (sequence of arrays): Arrays to be stacked. Each array is converted | |
| by :func:`cupy.atleast_2d` before stacking. | |
| dtype (str or dtype): If provided, the destination array will have this | |
| dtype. | |
| casting ({‘no’, ‘equiv’, ‘safe’, ‘same_kind’, ‘unsafe’}, optional): | |
| Controls what kind of data casting may occur. Defaults to | |
| ``'same_kind'``. | |
| Returns: | |
| cupy.ndarray: Stacked array. | |
| .. seealso:: :func:`numpy.dstack` | |
| """ | |
| return concatenate([cupy.atleast_2d(m) for m in tup], 0, | |
| dtype=dtype, casting=casting) | |
| def stack(tup, axis=0, out=None, *, dtype=None, casting='same_kind'): | |
| """Stacks arrays along a new axis. | |
| Args: | |
| tup (sequence of arrays): Arrays to be stacked. | |
| axis (int): Axis along which the arrays are stacked. | |
| out (cupy.ndarray): Output array. | |
| dtype (str or dtype): If provided, the destination array will have this | |
| dtype. Cannot be provided together with ``out``. | |
| casting ({‘no’, ‘equiv’, ‘safe’, ‘same_kind’, ‘unsafe’}, optional): | |
| Controls what kind of data casting may occur. Defaults to | |
| ``'same_kind'``. | |
| Returns: | |
| cupy.ndarray: Stacked array. | |
| .. seealso:: :func:`numpy.stack` | |
| """ | |
| return concatenate([cupy.expand_dims(x, axis) for x in tup], axis, out, | |
| dtype=dtype, casting=casting) | |