# numpy.ones_like¶

`numpy.``ones_like`(a, dtype=None, order='K', subok=True, shape=None)[source]

Return an array of ones with the same shape and type as a given array.

Parameters
aarray_like

The shape and data-type of a define these same attributes of the returned array.

dtypedata-type, optional

Overrides the data type of the result.

New in version 1.6.0.

order{‘C’, ‘F’, ‘A’, or ‘K’}, optional

Overrides the memory layout of the result. ‘C’ means C-order, ‘F’ means F-order, ‘A’ means ‘F’ if a is Fortran contiguous, ‘C’ otherwise. ‘K’ means match the layout of a as closely as possible.

New in version 1.6.0.

subokbool, optional.

If True, then the newly created array will use the sub-class type of a, otherwise it will be a base-class array. Defaults to True.

shapeint or sequence of ints, optional.

Overrides the shape of the result. If order=’K’ and the number of dimensions is unchanged, will try to keep order, otherwise, order=’C’ is implied.

New in version 1.17.0.

Returns
outndarray

Array of ones with the same shape and type as a.

See also

`empty_like`

Return an empty array with shape and type of input.

`zeros_like`

Return an array of zeros with shape and type of input.

`full_like`

Return a new array with shape of input filled with value.

`ones`

Return a new array setting values to one.

Examples

```>>> x = np.arange(6)
>>> x = x.reshape((2, 3))
>>> x
array([[0, 1, 2],
[3, 4, 5]])
>>> np.ones_like(x)
array([[1, 1, 1],
[1, 1, 1]])
```
```>>> y = np.arange(3, dtype=float)
>>> y
array([0., 1., 2.])
>>> np.ones_like(y)
array([1.,  1.,  1.])
```