| import numpy | |
| from cupy import _core | |
| def array_split(ary, indices_or_sections, axis=0): | |
| """Splits an array into multiple sub arrays along a given axis. | |
| This function is almost equivalent to :func:`cupy.split`. The only | |
| difference is that this function allows an integer sections that does not | |
| evenly divide the axis. | |
| .. seealso:: :func:`cupy.split` for more detail, :func:`numpy.array_split` | |
| """ | |
| return _core.array_split(ary, indices_or_sections, axis) | |
| def dsplit(ary, indices_or_sections): | |
| """Splits an array into multiple sub arrays along the third axis. | |
| This is equivalent to ``split`` with ``axis=2``. | |
| .. seealso:: :func:`cupy.split` for more detail, :func:`numpy.dsplit` | |
| """ | |
| if ary.ndim <= 2: | |
| raise ValueError('Cannot dsplit an array with less than 3 dimensions') | |
| return split(ary, indices_or_sections, 2) | |
| def hsplit(ary, indices_or_sections): | |
| """Splits an array into multiple sub arrays horizontally. | |
| This is equivalent to ``split`` with ``axis=0`` if ``ary`` has one | |
| dimension, and otherwise that with ``axis=1``. | |
| .. seealso:: :func:`cupy.split` for more detail, :func:`numpy.hsplit` | |
| """ | |
| if ary.ndim == 0: | |
| raise ValueError('Cannot hsplit a zero-dimensional array') | |
| if ary.ndim == 1: | |
| return split(ary, indices_or_sections, 0) | |
| else: | |
| return split(ary, indices_or_sections, 1) | |
| def split(ary, indices_or_sections, axis=0): | |
| """Splits an array into multiple sub arrays along a given axis. | |
| Args: | |
| ary (cupy.ndarray): Array to split. | |
| indices_or_sections (int or sequence of ints): A value indicating how | |
| to divide the axis. If it is an integer, then is treated as the | |
| number of sections, and the axis is evenly divided. Otherwise, | |
| the integers indicate indices to split at. Note that the sequence | |
| on the device memory is not allowed. | |
| axis (int): Axis along which the array is split. | |
| Returns: | |
| A list of sub arrays. Each array is a view of the corresponding input | |
| array. | |
| .. seealso:: :func:`numpy.split` | |
| """ | |
| if ary.ndim <= axis: | |
| raise IndexError('Axis exceeds ndim') | |
| size = ary.shape[axis] | |
| if numpy.isscalar(indices_or_sections): | |
| if size % indices_or_sections != 0: | |
| raise ValueError( | |
| 'indices_or_sections must divide the size along the axes.\n' | |
| 'If you want to split the array into non-equally-sized ' | |
| 'arrays, use array_split instead.') | |
| return array_split(ary, indices_or_sections, axis) | |
| def vsplit(ary, indices_or_sections): | |
| """Splits an array into multiple sub arrays along the first axis. | |
| This is equivalent to ``split`` with ``axis=0``. | |
| .. seealso:: :func:`cupy.split` for more detail, :func:`numpy.dsplit` | |
| """ | |
| if ary.ndim <= 1: | |
| raise ValueError('Cannot vsplit an array with less than 2 dimensions') | |
| return split(ary, indices_or_sections, 0) | |