1. MPE++: An Object-Oriented Mesh Partitioning Environment in C++ Shang-Hsien Hsieh, Yuan-Sen Yang, Wei-Choung Cheng, Ming-Der Lu, Elisa D. Sotelino Department of Civil Engineering National Taiwan University

2. Contents u Introduction – Mesh Partitioning Problem – MPE++ u Design of MPE++ – Object Classes in MPE++ – Collaborative Mechanism u Examples

3. Mesh Partitioning Problem u Task: – used for parallel finite element computations u Objectives: – obtaining a balanced distribution of workloads – minimizing communications

4. Introduction to MPE++ u Major Object Classes in MPE++ – Mesh – FEGraph – Partitioning – Evaluation – MpView

5. Mesh objects u Mesh object consists – Information models – Relationships among meshes and submeshes

6. FEGraph objects u FEGraph object – describes the topological information, by using FEGVertex and FEGEdge.

7. Partitioning objects u Partitioning Algorithms – Input: A Mesh – Output: A Mesh and its subMeshes

8. Partitioning objects (cont.) u RecursivePartitioning – require another Partitioning object as its kernel.

9. Evaluation & MpView objects u Evaluation – Input: a Mesh and its subMeshes – Output: numerical statistics, e.g. # of interface nodes. u MpView – Input: a Mesh and its subMeshes – Output: a 3D graphics window (based on OpenGL)

10. Collaborative Mechanism

11. Example void main () { InData in_data("lbuildin"); Mesh* mesh = in_data.mesh(); GR_Partitioning GR; GR.partition(mesh, 4); Evaluation eva(mesh); cout << "Tot(Nb):" << eva.num_boundary_nodes() << endl; MpView view(10,10,300,300,mesh); view.start(); } void main () { InData in_data("lbuildin"); Mesh* mesh = in_data.mesh(); GR_Partitioning GR; GR.partition(mesh, 4); Evaluation eva(mesh); cout << "Tot(Nb):" << eva.num_boundary_nodes() << endl; MpView view(10,10,300,300,mesh); view.start(); } Source code

12. Closure u MPE++ – Supports a flexible data management to ease the task of programming mesh partitioning algorithms. – Provides a consistent and easy-to-use programming interface. – Provides a set of graphics tools for visualization and evaluation of mesh partitioning results.

13. Acknowledgement u Support of U.S. Department of Energy under Award No. DE-FG02-93ER25169. u Support of R.O.C. National Science Council under the Project No. NSC86-2211-E-002- 029.