A simple finite element method library
Read mesh information generated by Triangle http://www.cs.cmu.edu/afs/cs.cmu.edu/project/quake/public/www/triangle.html

Read parameters from default input file

./tri

Read parameters from myinput.input

./tri myinput.input

Generate square mesh with normalized triangulation and refinement: first go to /meshgen, then compile in the normal way, run with the following where N is the number of columns and rows. Now it can only refine the leftmost column.

./meshgen N

Usage of tridiff.py

python tridiff.py -0 ./tri ./tri.input -1 "mpiexec -np 4 ./trimpi ./trimpi.input" -f ./meshgen/square.1.ma ./meshgen/square.1.rh ./meshgen/square.1.rrrr ./meshgen/square.1.output

It gives results like:

old and new ./meshgen/square.1.ma are identical
cmd1 did not modify ./meshgen/square.1.rh
cmd0 did not modify ./square.1.rrrr
change in ./meshgen/square.1.output
2c2
< 0.5 0.5 2.04766
---
> 0.5 0.5 2.1

Feb 24, 2015

• tri now works in parallel, check by "make trimpi"
• in DGSolvingSystemMPI, the stiff matrix is divided by row blocks, which consists with the data structure SuperLU_DIST uses, thus no explicit communication needed
• tridiff.py makes it easier to compare results generated by different solving systems or different parameters

Feb 21, 2015

• Separated the sparse linear system solver with fem solving system

Jan 25, 2015

• Rewrote definitions of most classes
• Temporarily removed the continuous FEM part which will be added after modification

May 27

• throw exceptions to gain better control of runtime error
• modified the output format in *.output

May 21

• correct the edge integral part, now deal with mesh with hanging nodes correctly
• code style formatted

May 16

• DG solver is able to deal with dirichlet boundary condition

May 15

• add the part of computing error in H1 norm
• remove template, clean some code and add some comments

May 14

• fix the part of computing error in L2 norm

Apr. 28

• the Discontinous Galerkin solving system can now deal with refinement with hanging nodes
• a simple tool to generate normalized mesh and refinement is provided, see usage
• users could specify refinement times and need to provide refinement information as is generated by the tool, meshgen, in *.ref0

Apr. 21

• added the function of the exact solution of the problem
• added the part of computing error
• added the parameter to control whether to compute and output error or not

Apr. 19

• modified all files with c++ template in order to deal with different problem definition for different schemes
• added a matlab visulization code plotTri.m
• added some sample mesh info files: dat/square.1.node, dat/square.1.ele, dat/square.1.edge

Apr. 18

• Added a Discontinuous Galerkin solving system
• a sample parameter file for DG tri.input, and for FEM triFEM.input

Mar. 28

• seperate BasicSolvingSystem and MySolvingSystem, rename the latter FEMSolvingSystem

Mar. 27

• add some parameters to gain control of input/output
• a sample parameter setting file is tri.input
• able to choose between UMFPACK and SuperLU to solve the spare matrix

Mar. 26

• the UMFPACK solving part is now working
• added SuperLU solving part
• rearranged some structure
• added some comments

Mar. 25

• version 0.01
• known problem: UMFPACK solving part does not work