[petsc-users] PetscMalloc with Fortran

[Barry Smith]

   Sorry it is missing in the fortran includes. You can use a short unsigned integer (16 bit) to represent it. I don’t know how that it is indicated in Fortran but a Fortran programmer would know.

Request-assigned: Satish, please add ISColoringValue to Fortran include; note that its value is configure assigned on the C side.

   Barry

On May 16, 2014, at 2:59 AM, Jonas Mairhofer <mairhofer at itt.uni-stuttgart.de> wrote:

> 
> 
> I tried to use ISColoringValue, but when I include
> 
> IScoloringValue   colors 
> 
> 
> into my code, I get an error message from the compiler(gfortran):
> 
> 
>      ISColoringValue colors
>       1
>     error: unclassifiable statement at (1)
> 
> I'm including these header files, am I missing one?
> 
> 
> #include <finclude/petscsys.h>
> #include <finclude/petscvec.h>
> #include <finclude/petscdmda.h>
> #include <finclude/petscis.h>
> #include <finclude/petscmat.h>
> #include <finclude/petscksp.h>
> #include <finclude/petscpc.h>
> #include <finclude/petscsnes.h>
> #include <finclude/petscvec.h90>
> #include <finclude/petscdmda.h90>
> 
> 
> 
> Thank you for your fast responses!
> 
> 
> 
> Am 15.05.2014 19:16, schrieb Peter Brune:
>> You should be using an array of type ISColoringValue. ISColoringValue is by default a short, not an int, so you're getting nonsense entries.  We should either maintain or remove ex5s if it does something like this.
>> 
>> - Peter
>> 
>> 
>> On Thu, May 15, 2014 at 11:56 AM, Jonas Mairhofer <mairhofer at itt.uni-stuttgart.de> wrote:
>> 
>> If 'colors' can be a dynamically allocated array then I dont know where
>> the mistake is in this code:
>> 
>> 
>> 
>> 
>> 
>>        ISColoring iscoloring
>>        Integer, allocatable :: colors(:)
>>        PetscInt maxc
>> 
>>       ...
>> 
>> 
>>       !calculate max. number of colors
>>       maxc = 2*irc+1 !irc is the number of ghost nodes needed to
>> calculate the function I want to solve
>> 
>>      allocate(colors(user%xm))  !where user%xm is the number of locally
>> owned nodes of a global array
>> 
>>      !Set colors
>>      DO i=1,user%xm
>>           colors(i) = mod(i,maxc)
>>      END DO
>> 
>>     call
>> ISColoringCreate(PETSC_COMM_WORLD,maxc,user%xm,colors,iscoloring,ierr)
>> 
>>     ...
>> 
>>     deallocate(colors)
>>     call ISColoringDestroy(iscoloring,ierr)
>> 
>> 
>> 
>> 
>> On execution I get the following error message (running the DO Loop from
>> 0 to user%xm-1 does not change anything):
>> 
>> 
>> [0]PETSC ERROR: --------------------- Error Message
>> ------------------------------------
>> [0]PETSC ERROR: Arguments are incompatible!
>> [0]PETSC ERROR: Number of colors passed in 291 is less then the actual
>> number of colors in array 61665!
>> [0]PETSC ERROR:
>> ------------------------------------------------------------------------
>> [0]PETSC ERROR: Petsc Release Version 3.4.4, Mar, 13, 2014
>> [0]PETSC ERROR: See docs/changes/index.html for recent updates.
>> [0]PETSC ERROR: See docs/faq.html for hints about trouble shooting.
>> [0]PETSC ERROR: See docs/index.html for manual pages.
>> [0]PETSC ERROR:
>> ------------------------------------------------------------------------
>> [0]PETSC ERROR: ./DFT on a arch-linux2-c-debug named
>> aries.itt.uni-stuttgart.de by mhofer Thu May 15 18:01:41 2014
>> [0]PETSC ERROR: Libraries linked from
>> /usr/ITT/mhofer/Documents/Diss/NumericalMethods/Libraries/Petsc/petsc-3.4.4/arch-linux2-c-debug/lib
>> [0]PETSC ERROR: Configure run at Wed Mar 19 11:00:35 2014
>> [0]PETSC ERROR: Configure options --with-cc=gcc --with-fc=gfortran
>> --download-f-blas-lapack --download-mpich
>> [0]PETSC ERROR:
>> ------------------------------------------------------------------------
>> [0]PETSC ERROR: ISColoringCreate() line 276 in
>> /usr/ITT/mhofer/Documents/Diss/NumericalMethods/Libraries/Petsc/petsc-3.4.4/src/vec/is/is/utils/iscoloring.c
>> 
>> 
>> 
>> 
>> 
>> But when I print out colors, it only has entries from 0 to 218, so no
>> entry is larger then 291 as stated in the error message.
>> 
>> 
>> 
>> 
>> 
>> 
>> 
>> 
>> 
>> 
>> Am 15.05.2014 16:45, schrieb Jed Brown:
>> 
>> Jonas Mairhofer <mairhofer at itt.uni-stuttgart.de> writes:
>> 
>> Hi, I'm trying to set the coloring of a matrix using ISColoringCreate.
>> Therefore I need an array 'colors' which in C can be creates as (from
>> example ex5s.c)
>> 
>> int *colors
>> PetscMalloc(...,&colors)
>> There is no PetscMalloc in Fortran, due to language "deficiencies".
>> 
>> colors(i) = ....
>> 
>> ISColoringCreate(...)
>> 
>> How do I have to define the array colors in Fortran?
>> 
>> I tried:
>> 
>> Integer, allocatable :: colors(:)    and    allocate() instead of
>> PetscMalloc
>> 
>> and
>> 
>> Integer, pointer :: colors
>> 
>> but neither worked.
>> The ISColoringCreate Fortran binding copies from the array you pass into
>> one allocated using PetscMalloc.  You should pass a normal Fortran array
>> (statically or dynamically allocated).
>> 
>> 
>