Re: [Numpy-discussion] Sum of the product of three or more arrays

2007-10-19 Thread Geoffrey Zhu
On 10/18/07, Robert Kern [EMAIL PROTECTED] wrote:
 Geoffrey Zhu wrote:
  Hi All,
 
  Given three vectors of the same lengths, X, Y, and Z, I am looking for
  an efficient way to calculate the following:
 
  sum(x[i]*y[i]*z[i], for i=1..n )

 (x*y*z).sum()

 --
 Robert Kern

 I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth.
  -- Umberto Eco
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Thanks Robert.

(x*y*z).sum() is probably faster than sum(x*y*z).
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Re: [Numpy-discussion] Sum of the product of three or more arrays

2007-10-18 Thread Robert Kern
Geoffrey Zhu wrote:
 Hi All,
 
 Given three vectors of the same lengths, X, Y, and Z, I am looking for
 an efficient way to calculate the following:
 
 sum(x[i]*y[i]*z[i], for i=1..n )

(x*y*z).sum()

-- 
Robert Kern

I have come to believe that the whole world is an enigma, a harmless enigma
 that is made terrible by our own mad attempt to interpret it as though it had
 an underlying truth.
  -- Umberto Eco
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Re: [Numpy-discussion] Sum of the product of three or more arrays

2007-10-18 Thread Geoffrey Zhu
I think I figured out: sum(X*Y*Z).

Never mind.

On 10/18/07, Geoffrey Zhu [EMAIL PROTECTED] wrote:
 Hi All,

 Given three vectors of the same lengths, X, Y, and Z, I am looking for
 an efficient way to calculate the following:

 sum(x[i]*y[i]*z[i], for i=1..n )


 I am not sure if there is a vectorized way to do this.

 Thanks,
 Geoffrey

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