If the matrices are not all the same size, then the order of
computation will make a difference. simple example: A is 1xn, B is
nx1, C is 1xn.
A(BC) takes n^3 multiplies, while (AB)C requires 2n.
albyn
Quoting Todd Schneider <todd.w.schnei...@gmail.com>:
Hi all,
I am looking for a function like cumprod() that works for matrix
multiplication.
In other words, I have matrices [M1, M2, ..., Mn], and I want to calculate
[M1, M1%*%M2, M1%*%M2%*%M3, ..., M1%*%...%*%Mn] as quickly as possible.
Right now I'm using a for() loop but it seems like there should be a faster
way.
Any help is appreciated!
Thanks,
Todd Schneider
todd.w.schnei...@gmail.com
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