← Back to team overview

dolfin team mailing list archive

[Bug 681415] Re: Problem using sub-spaces

 

I don't know if it's safe, but as for now it works, and for NS it can
give you speed-up of more than an order of magnitude. It does not work
in parallel of course.

Anyway, just wanted you to know that people are using the subfunction
functionality for more than setting boundary conditions:)

-- 
Problem using sub-spaces
https://bugs.launchpad.net/bugs/681415
You received this bug notification because you are a member of DOLFIN
Team, which is subscribed to DOLFIN.

Status in DOLFIN: Confirmed

Bug description:
Hi,

I have trouble using MixedFunctionSpace. Basically I want to project a function to a subspace of a MixedFunctionSpace:

   from dolfin import *
   mesh=UnitInterval(10)
   U = FunctionSpace(mesh, "CG", 1)
   V = FunctionSpace(mesh, "CG", 1)
   W=U*V
   f1=Function(W.sub(0))
   f1.vector()[:]=1.0
   #f2=project(f1, V)   # This works!
   f2=project(f1, W.sub(1))  # This doesn't!


The output of that script is attached to the end of this question. Now, the confusing thing is that the projection works fine if one projects to V instead of W.sub(1), although they are mathematically the same spaces. 

I hope I haven't missed a similar question already reported. 

Best wishes,

Simon


[0]PETSC ERROR: ------------------------------------------------------------------------
[0]PETSC ERROR: Caught signal number 11 SEGV: Segmentation Violation, probably memory access out of range
[0]PETSC ERROR: Try option -start_in_debugger or -on_error_attach_debugger
[0]PETSC ERROR: or see http://www.mcs.anl.gov/petsc/petsc-as/documentation/troubleshooting.html#Signal[0]PETSC ERROR: or try http://valgrind.org on GNU/linux and Apple Mac OS X to find memory corruption errors
[0]PETSC ERROR: configure using --with-debugging=yes, recompile, link, and run 
[0]PETSC ERROR: to get more information on the crash.
[0]PETSC ERROR: --------------------- Error Message ------------------------------------
[0]PETSC ERROR: Signal received!
[0]PETSC ERROR: ------------------------------------------------------------------------
[0]PETSC ERROR: Petsc Release Version 3.1.0, Patch 3, Fri Jun  4 15:34:52 CDT 2010
[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: Unknown Name on a linux-gnu named doodson by sf1409 Thu Nov 25 13:17:44 2010
[0]PETSC ERROR: Libraries linked from /build/buildd/petsc-3.1.dfsg/linux-gnu-c-opt/lib
[0]PETSC ERROR: Configure run at Fri Sep 10 04:57:14 2010
[0]PETSC ERROR: Configure options --with-shared --with-debugging=0 --useThreads 0 --with-clanguage=C++ --with-c-support --with-fortran-interfaces=1 --with-mpi-dir=/usr/lib/openmpi --with-mpi-shared=1 --with-blas-lib=-lblas --with-lapack-lib=-llapack --with-umfpack=1 --with-umfpack-include=/usr/include/suitesparse --with-umfpack-lib="[/usr/lib/libumfpack.so,/usr/lib/libamd.so]" --with-spooles=1 --with-spooles-include=/usr/include/spooles --with-spooles-lib=/usr/lib/libspooles.so --with-hypre=1 --with-hypre-dir=/usr --with-scotch=1 --with-scotch-include=/usr/include/scotch --with-scotch-lib=/usr/lib/libscotch.so --with-hdf5=1 --with-hdf5-dir=/usr
[0]PETSC ERROR: ------------------------------------------------------------------------
[0]PETSC ERROR: User provided function() line 0 in unknown directory unknown file
--------------------------------------------------------------------------
MPI_ABORT was invoked on rank 0 in communicator MPI_COMM_WORLD 
with errorcode 59.

NOTE: invoking MPI_ABORT causes Open MPI to kill all MPI processes.
You may or may not see output from other processes, depending on
exactly when Open MPI kills them.
--------------------------------------------------------------------------










Follow ups

References