[Numpy-discussion] help(numpy.dot) Hmmm.
Wayne Watson
sierra_mtnview at sbcglobal.net
Sun Dec 20 23:44:08 EST 2009
1.2.0. Did you find the description in the reference manual?
Charles R Harris wrote:
>
>
> On Sun, Dec 20, 2009 at 7:37 PM, Wayne Watson
> <sierra_mtnview at sbcglobal.net <mailto:sierra_mtnview at sbcglobal.net>>
> wrote:
>
> I've just become acquainted with the help command in WinXP IDLE.
> help(numyp.sin) works fine. What's going on with dot?
>
> >>> help(numpy.core.multiarray.dot)
> Help on built-in function dot in module numpy.core.multiarray:
>
> dot(...)
>
> Is there help for dot?
>
>
> Yes, but you may be using an old version of numpy. What does
> numpy.__version__ say? You can also find documentation on the
> scipy.org <http://scipy.org> site. Here is part of the current help:
>
> Help on built-in function dot in module numpy.core._dotblas:
>
> dot(...)
> dot(a, b)
>
> Dot product of two arrays.
>
> For 2-D arrays it is equivalent to matrix multiplication, and for 1-D
> arrays to inner product of vectors (without complex conjugation). For
> N dimensions it is a sum product over the last axis of `a` and
> the second-to-last of `b`::
>
> dot(a, b)[i,j,k,m] = sum(a[i,j,:] * b[k,:,m])
>
> Parameters
> ----------
> a : array_like
> First argument.
> b : array_like
> Second argument.
>
> Returns
> -------
> output : ndarray
> Returns the dot product of `a` and `b`. If `a` and `b` are both
> scalars or both 1-D arrays then a scalar is returned; otherwise
> an array is returned.
>
> Raises
> ------
> ValueError
> If the last dimension of `a` is not the same size as
> the second-to-last dimension of `b`.
>
> See Also
> --------
> vdot : Complex-conjugating dot product.
> tensordot : Sum products over arbitrary axes.
>
> Examples
> --------
> ...
>
> Chuck
>
> ------------------------------------------------------------------------
>
> _______________________________________________
> NumPy-Discussion mailing list
> NumPy-Discussion at scipy.org
> http://mail.scipy.org/mailman/listinfo/numpy-discussion
>
--
Wayne Watson (Watson Adventures, Prop., Nevada City, CA)
(121.015 Deg. W, 39.262 Deg. N) GMT-8 hr std. time)
Obz Site: 39° 15' 7" N, 121° 2' 32" W, 2700 feet
"... humans'innate skills with numbers isn't much
better than that of rats and dolphins."
-- Stanislas Dehaene, neurosurgeon
Web Page: <www.speckledwithstars.net/>
More information about the NumPy-Discussion
mailing list