There are quite a number of algorithms that use banded matricies and I would like to implement a few. I am using PDL because of its speed with large quantities of data.

Is there any particularly efficient way of initializing a banded matrix using PDL? It would be very useful to be able to define the entries of the matrix in terms of off-diagonals.

Eventually, I intend to implement my program with arbitrary dimensions of data, so I do not suppose anyone could help me write a program for creating a banded piddle with arbitrary (but symmetric) dimensionality?

For a banded matrix represented as matrix(i1,i2), it would be useful to specify the matrix elements (i1,i2) such that i1+n=i2. For the N dimensional generalization, one would specify the elements (i1,...iN) such that i1+n1=i2+n2=...=iN.

I am still quite new to PDL so I am not sure how best to go about doing this, so any help would be greatly appreciated.

In reply to How to make matrix/piddle/array with PDL or perl. by Feynman

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