On Wed, Oct 26, 2011 at 6:45 PM, Blaise Bourdin <span dir="ltr"><<a href="mailto:bourdin@lsu.edu">bourdin@lsu.edu</a>></span> wrote:<br><div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
Hi,<br>
<br>
We are slowly progressing in our attempt to use TS to solve evolution problems with our Sieve-based f90 unstructured element code, but are having a small problem. When we pass a DMMesh object to TSSetDM, we get the following error in TSSetup:<br>
<br>
[0]PETSC ERROR: DMCreateGlobalVector_Mesh() line 359 in src/dm/impls/mesh/mesh.c Must set default section<br>
<br>
Program received signal SIGABRT, Aborted.<br>
0x00007f0abdfdca75 in *__GI_raise (sig=<value optimized out>) at ../nptl/sysdeps/unix/sysv/linux/raise.c:64<br>
64 ../nptl/sysdeps/unix/sysv/linux/raise.c: No such file or directory.<br>
in ../nptl/sysdeps/unix/sysv/linux/raise.c<br>
(gdb) where<br>
#0 0x00007f0abdfdca75 in *__GI_raise (sig=<value optimized out>) at ../nptl/sysdeps/unix/sysv/linux/raise.c:64<br>
#1 0x00007f0abdfe05c0 in *__GI_abort () at abort.c:92<br>
#2 0x00007f0ac297207b in PetscAbortErrorHandler (comm=-2080374784, line=359, fun=0x7f0ac3a4dcf0 "DMCreateGlobalVector_Mesh", file=0x7f0ac3a4635e "mesh.c",<br>
dir=0x7f0ac3a46180 "src/dm/impls/mesh/", n=73, p=PETSC_ERROR_INITIAL, mess=0x7fff983d6080 "Must set default section", ctx=0x0) at errabort.c:62<br>
#3 0x00007f0ac296da19 in PetscError (comm=-2080374784, line=359, func=0x7f0ac3a4dcf0 "DMCreateGlobalVector_Mesh", file=0x7f0ac3a4635e "mesh.c", dir=0x7f0ac3a46180 "src/dm/impls/mesh/",<br>
n=73, p=PETSC_ERROR_INITIAL, mess=0x7f0ac3a464e8 "Must set default section") at err.c:356<br>
#4 0x00007f0ac2c5258c in DMCreateGlobalVector_Mesh (dm=0x20778a0, gvec=0x237d9c0) at mesh.c:359<br>
#5 0x00007f0ac2932b07 in DMCreateGlobalVector (dm=0x20778a0, vec=0x237d9c0) at dm.c:299<br>
#6 0x00007f0ac3143975 in SNESSetFunction (snes=0x237d7d0, r=0x0, func=0x7f0ac31f5f02 <SNESTSFormFunction(_p_SNES*, _p_Vec*, _p_Vec*, void*)>, ctx=0x2368a20) at snes.c:1153<br>
#7 0x00007f0ac31e5dc6 in TSSetIFunction (ts=0x2368a20, res=0x0, f=0x7f0ac32f0493 <ourifunction>, ctx=0x7fff983d6ee0) at ts.c:643<br>
#8 0x00007f0ac32f101e in tssetifunction_ (ts=0x7fff983d77d0, r=0x0, f=0x40dadb <ifunctionpoisson>, fP=0x7fff983d6ee0, ierr=0x7fff983d6bcc) at ztsf.c:158<br>
#9 0x000000000040e0d4 in tssetup (appctx=...) at m_TransientHeat.F90:376<br>
#10 0x000000000040b5fa in transientheat () at TransientHeat.F90:29<br>
#11 0x000000000047d3ea in main ()<br>
#12 0x00007f0abdfc7c4d in __libc_start_main (main=<value optimized out>, argc=<value optimized out>, ubp_av=<value optimized out>, init=<value optimized out>, fini=<value optimized out>,<br>
rtld_fini=<value optimized out>, stack_end=0x7fff983d7978) at libc-start.c:226<br>
#13 0x00000000004061b9 in _start ()<br>
<br>
My understanding is that we could address this problem in 2 ways<br>
1. Associating a default section to the mesh<br></blockquote><div><br></div><div>This is not hard. You can just take your solution section and call DMMeshSetSection(mesh, "default", solution).</div><div><br></div>
<div>The reason is that the DM wants to know how to create global vectors which hold solution values, etc. Somehow</div><div>the data layout must be communicated to the DM.</div><div><br></div><div> Matt</div><div> </div>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
2. Allocating the Solution vector, Jacobian matrix and so on by hand using the proper sieve--based functions, then passing them to the TS solver.<br>
but I have no idea how to do either one.<br>
<br>
Any suggestion? FWIW, in this test, both the IJacobian matrix and RHS Vector are constant, but this will not be the case once in the future.<br>
<br>
Something else bugging me is that the Jacobian function does not seem to be ever called (even in ex22 from src/ts/examples/tutorial). Is that expected? Is there a written description (or link to the literature) for each of the ODE solvers implemented in TS?<br>
<br>
Blaise<br>
<font color="#888888"><br>
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--<br>
Department of Mathematics and Center for Computation & Technology<br>
Louisiana State University, Baton Rouge, LA 70803, USA<br>
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</font></blockquote></div><br><br clear="all"><div><br></div>-- <br>What most experimenters take for granted before they begin their experiments is infinitely more interesting than any results to which their experiments lead.<br>
-- Norbert Wiener<br>