Re: More wierd behaviour from MatIsSymmetric?

["Matthew Knepley" <knepley@xxxxxxxxx>]

Is there a reason for not using 2.3.3? I suspect this to be a problem with
finite precision, which is corrected in the newest release.'

  Thanks,

    Matt

On 10/17/07, Toby D. Young <tyoung@xxxxxxxxxxx> wrote:
>
>
> I am having a little trouble, or confusion, with the MatIsSymmetric
> function. I am getting the reverse behaviour from this routine that I
> expect. I am convinced I have a symmetric matrix, but the answer I get
> from this function is always zero - ie, PetscTruth = PetscFalse.
>
> Why, if PETSC_YES is an alias for PETSC_TRUE, do they have opposite
> behaviour according to the documentation? That doen't seem right. What
> is the idea here?
>
> I there an error in the documentation, or am I misunderstanding
> something? I appreceate your usually helpful remarks!!
>
> For reference, please see:
> http://www-unix.mcs.anl.gov/petsc/petsc-as/snapshots/petsc-current/include/petsc.h.html#PetscTruth
> Or the notes written below.
>
> Using petsc 2.3.0;
> Best,
>         Toby
>
>
> 339: /*MC
> 340:     PETSC_TRUE - True value of PetscTruth
>
> 342:     Level: beginner
>
> 344:     Note: Nonzero integer
>
> 346: .seealso: PetscTruth, PETSC_FALSE
> 347: M*/
>
> 349: /*MC
> 350:     PETSC_YES - Alias for PETSC_TRUE
>
> 352:     Level: beginner
>
> 354:     Note: Zero integer
>
> 356: .seealso: PetscTruth, PETSC_TRUE, PETSC_FALSE, PETSC_NO
> 357: M*/
>
>
> --
>
> Toby D. Young - Adiunkt (Assistant Professor)
> Department of Computational Science
> Institute of Fundamental Technological Research
> Polish Academy of Sciences
> Room 206, Swietokrzyska 21
> 00-049 Warsaw, POLAND
>
>


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