numpy.ma.ones

numpy.ma.ones(shape, dtype=None, order='C') = <numpy.ma.core._convert2ma object>

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

Parameters:
shape : int or sequence of ints

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

dtype : data-type, optional

The desired data-type for the array, e.g., numpy.int8. Default is numpy.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:
out : ndarray

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

参见

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.]])