[petsc-users] Finding determinant and inverse matrix

[Matthew Knepley]

On Wed, Aug 4, 2010 at 12:18 PM, Немања Илић (Nemanja Ilic) <
nemanja.ilic.81 at gmail.com> wrote:

> Hello,
>
> Thank you for you previous help. I wrote the code for calculating matrix
> determinant and inverse matrix and they don't break anymore. Still I have
> problems. I try to find determinant in the following way: First get LU
> factor of a matrix and then multiply it's diagonal elements. I don't get
> correct results. Could you tell me wheather the problem


That description does not help. What do you get? What is the correct answer?
Did you try it on a small
problem that you can factor by hand?


> is maybe in info structure? What information do you need to be able to help
> me? I find the inverse matrix in the following way: I create linear problem
> A * X = B where A is the input matrix, X is the inverse matrix, and B is
> identity matrix. I solve it using MatMatSolve. Could you possibly help me
> and what info do you need?
>

That should work.

   Matt


> Thank you in advance,
> Best regards,
> Nemanja
>



-- 
What most experimenters take for granted before they begin their experiments
is infinitely more interesting than any results to which their experiments
lead.
-- Norbert Wiener
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