numpy.ones — NumPy v1.18 Manual (original) (raw)

numpy. ones(shape, dtype=None, order='C')[source]¶

Return a new array of given shape and type, filled with ones.

Parameters

shapeint or sequence of ints

Shape of the new array, e.g., (2, 3) or 2.

dtypedata-type, optional

The desired data-type for the array, e.g., numpy.int8. Default isnumpy.float64.

order{‘C’, ‘F’}, optional, default: C

Whether to store multi-dimensional data in row-major (C-style) or column-major (Fortran-style) order in memory.

Returns

outndarray

Array of ones with the given shape, dtype, and order.

See also

ones_like

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

empty

Return a new uninitialized array.

zeros

Return a new array setting values to zero.

full

Return a new array of given shape filled with value.

Examples

np.ones(5) array([1., 1., 1., 1., 1.])

np.ones((5,), dtype=int) array([1, 1, 1, 1, 1])

np.ones((2, 1)) array([[1.], [1.]])

s = (2,2) np.ones(s) array([[1., 1.], [1., 1.]])