split

split(ary, indices_or_sections, axis=0)

Split an array into multiple sub-arrays.

Parameters:

ary : ndarray

Array to be divided into sub-arrays.

indices_or_sections : int or 1-D Python tuple, list or set.

If indices_or_sections is an integer, N, the array will be divided into N equal arrays along axis. If such a split is not possible, an error is raised. If indices_or_sections is a 1-D array of sorted integers, the entries indicate where along axis the array is split. For example, [2, 3] would, for axis=0, result in

• ary[:2]
• ary[2:3]
• ary[3:]

If an index exceeds the dimension of the array along axis, an empty sub-array is returned correspondingly.

axis : int, optional

The axis along which to split, default is 0.

Returns:

sub-arrays : list of ndarrays

A list of sub-arrays.

Raises:

ValueError

If indices_or_sections is given as an integer, but a split does not result in equal division.

See also

hsplit

Split array into multiple sub-arrays horizontally (column-wise).

vsplit

Split array into multiple sub-arrays vertically (row wise).

dsplit

Split array into multiple sub-arrays along the 3rd axis (depth).

concatenate

Join a sequence of arrays along an existing axis.

stack

Join a sequence of arrays along a new axis.

hstack

Stack arrays in sequence horizontally (column wise).

vstack

Stack arrays in sequence vertically (row wise).

dstack

Stack arrays in sequence depth wise (along third dimension).

Examples

>>> x = np.arange(9.0)
>>> np.split(x, 3)
[array([0., 1., 2.]), array([3., 4., 5.]), array([6., 7., 8.])]

>>> np.split(x, [3, 5, 6, 8])
[array([0., 1., 2.]), array([3., 4.]), array([5.]), array([6., 7.]), array([])]