[petsc-users] question about the most effective implementation

[Michael Povolotskyi]

Thank you Barry and Jed,

I think I'll go with MatDiagonalScale.

Michael.


On 06/20/2018 02:06 PM, Jed Brown wrote:
> Michael Povolotskyi <mpovolot at purdue.edu> writes:
>
>> Dear Petsc team,
>>
>> what would be the most efficient way to compute the following:
>>
>> V += A*B*C,
>>
>> where V is a dense square matrix,
>>
>> B is a square diagonal matrix, A and C are dense rectangular matrices?
>>
>> I would like to benefit from the fact that B is diagonal.
> MatDiagonalScale.  No matter what you do, the cost will be dominated by the dense product.