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Re: PETSc sparsity

Just a note, my way is much simpler - its two lines of code in a loop over the boundary nodes, followed by an MatAsseblyBegin/End, and you don't have to deal with parallel issues explicitly - PETSc does. For my FE codes the cost of this (dumb) way is negligible, PETSc implements these methods pretty well.

Mark

On Jun 15, 2007, at 4:28 PM, Toby Young wrote:



Barry,

Thank you for an interesting response.

For algorithms that require dealing with the sparsity structure of
the matrix we generally just include the appropriate private include file
for the matrix format and access the data directly in the underlying format. 

Can you please elaborate. What do you mean by "the appropriate privat
include file for the matrix"? Sorry, I got lost there.

Best,
	Toby

-----

Toby D. Young (Adiunkt)
Department of Computational Science
Institute of Fundamental Technological Research
Polish Academy of Science
Room 206, ul. Swietokrzyska 21
00-049 Warszawa, POLAND


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