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Topic: Multi-dimensional array product
Replies: 5   Last Post: Nov 15, 2012 8:23 AM

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 Ed Stein7997 Posts: 1 Registered: 8/16/09
Multi-dimensional array product
Posted: Aug 16, 2009 8:24 PM

I have a question about how to efficiently form multi-dimensional arrays.

Lets say I have two 2-d arrays (i.e. matrices) a and b; a(i,j) sized
i=1..M,j=1..N; and b(i,j) sized i=1..K,j=1..L.

How can I form the 4-d array w(m,n,k,l)=a(m,n)*b(k,l) which has a unique
entry for every m,n,k,l; i.e. there are M*N*K*L unique entries?

I want to form w in a 'vectorized' way without use of loops. A
conventional matrix product like a*b doesn't work of course since the
inner dimensions of a and b aren't the same. This isn't the same as a
Kronecker product since that remains two-dimensional.

Thanks for any assistance.

Ed Stein
edstein7997@hushmail.com

Date Subject Author
8/16/09 Ed Stein7997
8/16/09 Doug Schwarz
8/16/09 arun
8/16/09 arun
8/17/09 Matt
11/15/12 Gustaf