[ODE] Matrix * vector?

Francisco Jesús Martínez Serrano franjesus at medtelecom.net
Thu Jun 19 16:54:02 2003


El Jueves, 19 jun, 2003, a las 20:23 Europe/Madrid, Amund Børsand 
escribió:

>
> Is there a function in ODE to multiply a vector by a matrix (the
> standard thing to do to rotate a vector by a matrix) ?

dMultiply0, dMultiply1, dMultiply2.

To rotate a vector V by a matrix M, try:

dMultiply0(Result,M,V,3,3,1);

To multiply matrices together use instead:

dMultiply0(Result,M1,M2,3,3,3);

If you want to do it while transposing at the same time the matrix, use 
dMultiply1, dMultiply2 transposes both arguments (I believe, don't 
remember well).

Try grepping the ode source-code for dMultiply0 or dMULTIPLY0_331. If I 
remember correctly, they are documented in the comments.

Cheers.