Search All of the Math Forum:

Views expressed in these public forums are not endorsed by NCTM or The Math Forum.

Notice: We are no longer accepting new posts, but the forums will continue to be readable.

Topic: efficiently multiplying matrices
Replies: 3   Last Post: Nov 10, 2004 10:19 AM

 Messages: [ Previous | Next ]
 marquito Posts: 11 Registered: 1/25/05
efficiently multiplying matrices
Posted: Nov 10, 2004 7:10 AM

Hi!

I'd like to multiply matrices the following way:
Ai, Bi = 3x3 real matrices

A1'*B1, A2'*B2 ... An'*Bn

those matrices are located in two big matrices:
A = (A1;A2;...;An) = 3*n x 3 matrix
B = (B1;B2;...;Bn) = 3*n x 3 matrix

Is there a way to do it without a loop? One possibility is to
contruct 2 matrices like:

A = A1 0 0 ..... 0
0 A2 0 .... 0
0 0 A3 ....0
.............
. ...........
. . . . . . An

and do the multiplication A'*B

Is there some nice and elegant way to do it? Any other hints maybe?

Date Subject Author
11/10/04 marquito
11/10/04 Ken Davis
11/10/04 Peter Boettcher
11/10/04 marquito