matrix multiplication (newbie question)

Johannes Loehnert a.u.r.e.l.i.a.n at gmx.net
Wed Nov 8 10:16:17 CST 2006


Hi,

in extension to the previous answers, I'd like to say that it is strongly 
preferable to use dot(A,dot(B,C)) or dot(dot(A,B),C) instead of A*B*C.

The reason is that with dot(), you can control of which operation is performed 
first, which can *massively* influence the time needed, depending on the 
involved matrices. A*B*C will always be evaluated left-to-right (if I 
remember correctly).

Johannes

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