On Fri, Feb 10, 2012 at 4:02 PM, Jed Brown <[email protected]> wrote:

On Fri, Feb 10, 2012 at 15:59, Dmitry Karpeev <[email protected]> wrote:

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As a separate matter, however, should preallocated, but not assembled matrices be able to be duplicated or copied?

It doesn't even make semantic sense for Copy.

Fine.

Duplicate only makes sense in that the sizes and types get set, but obviously the sparsity can't be set, so it doesn't have the (stated) semantics of Duplicate.

I'm not sure I follow. If a matrix has been created, its type has been set and it has been preallocated (e.g., MATMPIAIJ in ksp/ksp/examples/tutorials/ex2), it is not marked as assembled until after MatAssemblyEnd. Does it still make sense to duplicate it? In my opinion, it does. Dmitry.

As currently implemented, MatDuplicate() and MatCopy() will refuse to

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operate on a matrix that is !assembled.