On Mon, Feb 17, 2020 at 4:33 PM Emmanuel Ayala wrote:
> Hi,
>
> Thank you for the clarification, now I understand what means change those
> values, and I tried to do that.
>
> But if I put the row i to the identity in A, and zero in B, the solver
> crash:
>
So if you need to factor B, maybe
> On Feb 17, 2020, at 7:56 AM, Yuyun Yang wrote:
>
> Hello,
>
> I actually have a question about the usage of DMDA since I'm quite new to
> this. I wonder if the DMDA suite of functions can be directly called on
> vectors created from VecCreate?
Yes, but you have to make sure the ones
Hi,
Thank you for the clarification, now I understand what means change those
values, and I tried to do that.
But if I put the row i to the identity in A, and zero in B, the solver
crash:
[0]PETSC ERROR: - Error Message
Awesome - thanks for that. I will check it out. I will also look at what
needs to be done to bring simulatrophy to a more recent version of petsc.
On Tue, 18 Feb 2020 at 03:19, Junchao Zhang wrote:
> Hi, Richard,
> I tested the case you sent over and found it did fail due to the 32-bit
>
You can create a dense matrix and use VecPlaceArray() to take a column out of
the matrix as a vector. For example,
MatCreateDense()
MatDenseGetColumn(A,0,col)
VecPlaceArray(v,col)
… // fill in the vector with values
VecResetArray(v)
MatDenseRestoreColumn(A,)
Hong (Mr.)
> On Feb 17, 2020, at
On Mon, Feb 17, 2020 at 1:59 PM Emmanuel Ayala wrote:
> Hi, thanks for the quick answer.
>
> I just did it, and it does not work. My problem is GNHEP and I use the
> default solver (Krylov-Schur). Moreover I run the code with the options:
> -st_ksp_type preonly -st_pc_type lu
Hi, thanks for the quick answer.
I just did it, and it does not work. My problem is GNHEP and I use the
default solver (Krylov-Schur). Moreover I run the code with the options:
-st_ksp_type preonly -st_pc_type lu -st_pc_factor_mat_solver_type mumps
Any other suggestions?
Kind regards.
El lun.,
The usual trick is to set ones in one matrix and zeros in the other
one.
On Mon, 2020-02-17 at 12:35 -0600, Emmanuel Ayala wrote:
> Hi everyone,
>
> I have an eigenvalue problem where I need to apply BCs to the
> stiffness and mass matrix.
>
> Usually, for KSP solver, it is enough to set to
Hi everyone,
I have an eigenvalue problem where I need to apply BCs to the stiffness and
mass matrix.
Usually, for KSP solver, it is enough to set to zero the rows and columns
related to the boundary conditions. I used to apply it with
MatZeroRowsColumns, with a 1s on the diagonal. Then the
Thank you very much for the answer.
This error appears when computing the B-norm of a vector x, as
> sqrt(x'*B*x). Probably your B matrix is semi-definite, and due to
> floating-point error the value x'*B*x becomes negative for a certain vector
> x. The code uses a tolerance of
Hi, Richard,
I tested the case you sent over and found it did fail due to the 32-bit
overflow on number of non-zeros, and with a 64-bit built petsc it passed.
You had a typo when you reported that --with-64-bit-indicies=yes failed. It
should be --with-64-bit-indices=yes.
You can go with a 64-bit
On Mon, Feb 17, 2020 at 8:56 AM Yuyun Yang wrote:
> Hello,
>
> I actually have a question about the usage of DMDA since I'm quite new to
> this. I wonder if the DMDA suite of functions can be directly called on
> vectors created from VecCreate? Or the vectors have to be formed by
>
Hello,
I actually have a question about the usage of DMDA since I'm quite new to this.
I wonder if the DMDA suite of functions can be directly called on vectors
created from VecCreate? Or the vectors have to be formed by
DMDACreateGlobalVector? I'm also not sure about what the dof and stencil
On Mon, Feb 17, 2020 at 4:24 AM Jose E. Roman wrote:
> I would use MatDenseGetColumn() and VecGetArrayRead() to get the two
> pointers and then copy the values with a loop.
>
I would do as Jose says to get it working. After you verify it, we could
show you how to avoid a copy.
Thanks,
I would use MatDenseGetColumn() and VecGetArrayRead() to get the two pointers
and then copy the values with a loop.
Jose
> El 17 feb 2020, a las 9:35, Eda Oktay escribió:
>
> Hello all,
>
> I am trying to form a matrix whose columns are eigenvectors I have calculated
> before U =
Hello all,
I am trying to form a matrix whose columns are eigenvectors I have
calculated before U = [v1,v2,v3]. Is there any easy way of forming this
matrix? My matrix should be parallel and I have created vectors as below,
where nev i s the number of requested eigenvalues. So each V[i]
16 matches
Mail list logo