Timeline for Thomas algorithm for 3D finite difference
Current License: CC BY-SA 3.0
8 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Oct 3, 2016 at 15:45 | vote | accept | Lukas Bystricky | ||
| Sep 27, 2016 at 8:00 | history | tweeted | twitter.com/StackSciComp/status/780678566824570880 | ||
| Sep 26, 2016 at 19:34 | comment | added | Abhilash Reddy M | What PDE do you want to solve? For diffusion problems, you might be able to use alternating-direction-implicit (ADI) methods. It would allow to apply Thomas algorithm to 3D problems (at the cost of being restricted to 2nd order spatial accuracy.) | |
| Sep 25, 2016 at 1:46 | answer | added | Wolfgang Bangerth | timeline score: 6 | |
| Sep 24, 2016 at 22:55 | comment | added | Bill Greene | What is your objective? If it is to compute a solution to your equations with minimal CPU time, I suggest you simply call the Lapack routine dgbsv in a high-performance implementation of Lapack/BLAS (e.g. OpenBLAS or MKL) and be done with it. | |
| Sep 24, 2016 at 21:50 | comment | added | Lukas Bystricky | Right, it would be a banded matrix so of course the algorithm wouldn't be identical. The reference I posted (section 3.8) goes over some variations for banded systems. I'm just trying to work out the implementation. | |
| Sep 24, 2016 at 21:02 | comment | added | Kirill | The point of Thomas algorithm, which is really just a special-cased GE/LU for a tridiagonal matrix, is that a tridiagonal matrix has tridiagonal LU decomposition. But a 3d finite difference matrix wouldn't have a tridiagonal LU decomposition, it would be $n^2$-banded. | |
| Sep 24, 2016 at 17:35 | history | asked | Lukas Bystricky | CC BY-SA 3.0 |