resolving zexy vs cyclone (was [PD-dev] cvs admin question ...)

Mathieu Bouchard matju at sympatico.ca
Thu Mar 3 22:14:54 CET 2005


On Thu, 3 Mar 2005, IOhannes m zmoelnig wrote:
> Winfried Ritsch wrote:
> jfyi: the major inconsistancy with zexy's [matrix~] is, that when 
> multiplying a vector of signals with a matrix the actual operation that 
> takes place is "x^ = a^ * A", while in literature normally we find 
> things like "y^ = B * b^", which is only the same if we assume x^=y^' 
> and A=B'.

GridFlow's @inner was originally doing something like the latter, actually
R = A*transpose(B), of which the latter is a special case (because of the
commutativity of Real Dot Product).

At a certain point in 2002, I changed it so that @inner is R=A*B, and
@inner2 is R=A*transpose(B). In the new system (2005) there is #inner and
#transpose.

The other differences are that matrix~ is for signals only, and handles
only two dimensions.

> anyone has an idea how to find an elegant solution to this problem 
> (while still maintaining an intuitive object) ?

just write your matrices pretransposed.

_____________________________________________________________________
Mathieu Bouchard -=- Montréal QC Canada -=- http://artengine.ca/matju





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