Function empty

numpy/matlib.py:25–64

Return a new matrix of given shape and type, without initializing entries. Parameters ---------- shape : int or tuple of int Shape of the empty matrix. dtype : data-type, optional Desired output data-type. order : {'C', 'F'}, optional Whether to store mul

(shape, dtype=None, order='C')

__all__ += np.__all__

def empty(shape, dtype=None, order='C'):
    """Return a new matrix of given shape and type, without initializing entries.

    Parameters
    ----------
    shape : int or tuple of int
        Shape of the empty matrix.
    dtype : data-type, optional
        Desired output data-type.
    order : {'C', 'F'}, optional
        Whether to store multi-dimensional data in row-major
        (C-style) or column-major (Fortran-style) order in
        memory.

    See Also
    --------
    numpy.empty : Equivalent array function.
    matlib.zeros : Return a matrix of zeros.
    matlib.ones : Return a matrix of ones.

    Notes
    -----
    Unlike other matrix creation functions (e.g. `matlib.zeros`,
    `matlib.ones`), `matlib.empty` does not initialize the values of the
    matrix, and may therefore be marginally faster. However, the values
    stored in the newly allocated matrix are arbitrary. For reproducible
    behavior, be sure to set each element of the matrix before reading.

    Examples
    --------
    >>> import numpy.matlib
    >>> np.matlib.empty((2, 2))    # filled with random data
    matrix([[  6.76425276e-320,   9.79033856e-307], # random
            [  7.39337286e-309,   3.22135945e-309]])
    >>> np.matlib.empty((2, 2), dtype=np.int_)
    matrix([[ 6600475,        0], # random
            [ 6586976, 22740995]])

    """
    return ndarray.__new__(matrix, shape, dtype, order=order)

def ones(shape, dtype=None, order='C'):
    """