Matrix objects (1)

NumPy has an array type, matrix, much like Matlab's array type

>>> x1 = array([1, 2, 3], float)
>>> x2 = matrix(x1)               # or just mat(x)
>>> x2                            # row vector
matrix([[ 1.,  2.,  3.]])
>>> x3 = matrix(x1.transpose()    # column vector
>>> x3                             
matrix([[ 1.],
        [ 2.],
        [ 3.]])

>>> type(x3)
<class 'numpy.core.defmatrix.matrix'>
>>> isinstance(x3, matrix)
True

Only 1- and 2-dimensional arrays can be matrix