On Wed, Jul 4, 2012 at 12:15 AM, Luigia Ambrosio <[email protected]>wrote:

this is the source code (very simple) Vec x; PetscInt n = 10; PetscErrorCode ierr; PetscScalar one = 1.0;

ierr = VecCreateMPI(PETSC_COMM_WORLD, PETSC_DECIDE, n, &x);CHKERRQ(ierr); ierr = VecSet(x,one);CHKERRQ(ierr); PetscScalar sum=0.0; ierr = VecSum(x,&sum);CHKERRQ(ierr); ierr = PetscPrintf(PETSC_COMM_WORLD,"sum %f\n",(PetscRealPart)sum);

Use PetscRealPart(sum), it is a function, not a type.

CHKERRQ(ierr); puts("");

This puts will be issued by every process, leading to messy output, especially for larger runs. Just add a second \n to the string passed to PetscPrintf() if you want another newline.

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and this is the error message I get trying make myex error: 'PetscRealPart' was not declared in this scope

this is how I compile myex myex: myex.o chkopts -${CLINKER} -o myex myex.o ${PETSC_VEC_LIB} ${RM} -f myex.o

I have petsc 3.3 developer version

Luigia Ambrosio

Se la gente ferisce è perchè tu sei migliore e lo capisce bene! - Tiziano Ferro

Il giorno 04/lug/2012, alle ore 09:58, Jed Brown ha scritto:

On Tue, Jul 3, 2012 at 11:53 PM, Luigia Ambrosio < [email protected]> wrote:

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It seems I don't have this function. I checked my configuring options, in particular --with-scalar-type=complex

Which version of PETSc? Can you send the full error message?

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so I'm sure that a PetscScalar variable is handled as a complex number. I tried to use the PetscRealPart but it says: error: 'PetscRealPart' was not declared in this scope

I included also the header "petscmat.h" but there isn't defined this function. It seems that I don't include the right header, I googled it but I didn't find it. Which header shiuld I include?

That header includes petscmath.h (which you should not include directly).

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thanks

Luigia Ambrosio

Se la gente ferisce è perchè tu sei migliore e lo capisce bene! - Tiziano Ferro

Il giorno 04/lug/2012, alle ore 09:28, Jed Brown ha scritto:

On Tue, Jul 3, 2012 at 11:26 PM, Luigia Ambrosio < [email protected]> wrote:

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Is there a function already avilable to get the real part of a petscscalar value?

PetscRealPart() and PetscImaginaryPart()