[Numpy-discussion] dot function or dot notation, matrices, arrays?

Wayne Watson sierra_mtnview@sbcglobal....
Fri Dec 18 17:40:56 CST 2009

Well, they aren't quite the same. If a is the length of A, and b is the 
length of B, then a*b = A dot B* cos (theta).  I'm still not familiar 
enough with numpy or math to know if there's some function that will 
produce a from A. It's easy enough to do, a = A(0)**2 + ..., but I would 
like to think it's a common enough need that there would be something 
available like sumsq().

Keith Goodman wrote:
> On Fri, Dec 18, 2009 at 3:22 PM, Wayne Watson
> <sierra_mtnview@sbcglobal.net> wrote:
>> Is there a scalar product in numpy?
> Isn't that the same thing as a dot product? np.dot doesn't do what you want?
> _______________________________________________
> NumPy-Discussion mailing list
> NumPy-Discussion@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