[Numpy-discussion] matrix indexing question

Alan G Isaac aisaac@american....
Sun Mar 25 12:07:25 CDT 2007


One thing keeps bugging me when I use numpy.matrix.

All this is fine::

    >>> x=N.mat('1 1;1 0')
    >>> x
    matrix([[1, 1],
            [1, 0]])
    >>> x[1,:]
    matrix([[1, 0]])

But it seems to me that I should be able
to extract a matrix row as an array.
So this ::

    >>> x[1]
    matrix([[1, 0]])

feels wrong.  (Similarly when iterating across rows.)
Of course I realize that I can just ::

    >>> x.A[1]
    array([1, 0])

but since the above keeps feeling wrong I felt I should 
raise this as a possible design issue, better discussed
early than latter.

Cheers,
Alan Isaac




More information about the Numpy-discussion mailing list