[R] Matrix mulitplication
(Ted Harding)
Ted.Harding at nessie.mcc.ac.uk
Tue Feb 17 00:41:57 CET 2004
On 16-Feb-04 Peter Dalgaard wrote:
> (Ted Harding) <Ted.Harding at nessie.mcc.ac.uk> writes:
>
>> Sorry! Missed a trick here:
>>
>> At <- t(A)
>> Bt <- t(B)
>> E <- B%*%A
>> Et <- t(E)
>> A%*%solve(Et%*%E + C)%*%Et%*%D
>>
>> (saves 2 multiplications at the relatively cheap cost of 1 transpose)
>
> Well, you might consider getting rid of the first two transposes since
> you're not actually using them for anything....
Touché ... !
Ted.
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Date: 16-Feb-04 Time: 23:41:57
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