[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?
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>   

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           Wayne Watson (Watson Adventures, Prop., Nevada City, CA)

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