[petsc-users] removing small entries from a sparse matrix

[Barry Smith]

On Dec 30, 2009, at 2:35 AM, Dominik Szczerba wrote:

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> Have there been any studies in that matter? Anything I should cite to
> justify such choice?

   Not that I know of.

    Barry

>
> Dominik
>
> Barry Smith wrote:
>>   Keep the small values. The nonzero structure will also help the
>> convergence of most preconditioners.
>>
>>    Barry
>>
>> On Dec 29, 2009, at 4:38 PM, Dominik Szczerba wrote:
>>
>> Is it possible to remove small (subject to given tol) entries in my
>> sparse coefficient matrix after the values have been set (added)? I
>> have
>> a highly convective problem where I ask myself what's better, keep
>> lots
>> of explicit zeros to rescue constant non-zero pattern or eliminate  
>> the
>> near-zero entries.
>> Dominik
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