From 7d45d0d51c63b24d1fc1d5a68c9543a0e6dc4c89 Mon Sep 17 00:00:00 2001 From: bangerth Date: Wed, 17 Nov 2010 03:57:13 +0000 Subject: [PATCH] Add the last missing paragraph. git-svn-id: https://svn.dealii.org/trunk@22786 0785d39b-7218-0410-832d-ea1e28bc413d --- deal.II/examples/step-40/doc/results.dox | 52 +++++++++++++++++++++++- 1 file changed, 51 insertions(+), 1 deletion(-) diff --git a/deal.II/examples/step-40/doc/results.dox b/deal.II/examples/step-40/doc/results.dox index 1f6ec4ad75..ca42bb0ecc 100644 --- a/deal.II/examples/step-40/doc/results.dox +++ b/deal.II/examples/step-40/doc/results.dox @@ -1,6 +1,56 @@

Results

-DOCUMENT HOW TO RUN THE PROGRAM +When you run the program, on a single processor or with your local MPI +installation on a few, you should get output like this: +@code +Cycle 0: + Number of active cells: 1024 + Number of degrees of freedom: 4225 + Solved in 10 iterations. + +Cycle 1: + Number of active cells: 1954 + Number of degrees of freedom: 8399 + Solved in 11 iterations. + +Cycle 2: + Number of active cells: 3640 + Number of degrees of freedom: 16091 + Solved in 11 iterations. + +Cycle 3: + Number of active cells: 7018 + Number of degrees of freedom: 31387 + Solved in 11 iterations. + +Cycle 4: + Number of active cells: 13594 + Number of degrees of freedom: 61531 + Solved in 13 iterations. + +Cycle 5: + Number of active cells: 26950 + Number of degrees of freedom: 122693 + Solved in 13 iterations. + +Cycle 6: + Number of active cells: 54373 + Number of degrees of freedom: 248265 + Solved in 14 iterations. + +Cycle 7: + Number of active cells: 111754 + Number of degrees of freedom: 513153 + Solved in 14 iterations. +@endcode + +The exact numbers differ, depending on how many processors we use; +this is due to the fact that the preconditioner depends on the +partitioning of the problem, the solution then differs in the last few +digits, and consequently the mesh refinement differs slightly. +The primary thing to notice here, though, is that the number of +iterations does not increase with the size of the problem. This +guarantees that we can efficiently solve even the largest problems. When run on a sufficiently large number of machines (say a few thousand), this program can relatively easily solve problems with well -- 2.39.5