thomas algorithm

cvkeshav · March 28, 2009, 07:14

Hey, im working on a tridiagonal solver, aka the Thomas Algorithm to solve boundary value problems for my graduate course in cfd at the university of arizona. I am writing my codes in c++. the problem with my code is that my solution oscillates at every point, one a negative value and the next being a positive value, all through my domain. this is very weird to me and i dont know what to do...
Thanks for your help in advance.
C.V.Keshav

mr_fluent · March 28, 2009, 08:48

take a look at the algo given at our wiki reference. That algorithm works well because i am using it now a days without any problems. In fact my new solver works heavly around it and it performs beautifully.

Check your coefficients carefully by printing them, or use this algo to validate small test problem first.

cvkeshav · March 29, 2009, 05:37

Hey, I found the error in my code. It is working fine now. Thanks.

March 28, 2009, 07:14	thomas algorithm	#1
cvkeshav New Member C.V.Keshav Join Date: Mar 2009 Posts: 2 Rep Power: 0	Hey, im working on a tridiagonal solver, aka the Thomas Algorithm to solve boundary value problems for my graduate course in cfd at the university of arizona. I am writing my codes in c++. the problem with my code is that my solution oscillates at every point, one a negative value and the next being a positive value, all through my domain. this is very weird to me and i dont know what to do... Thanks for your help in advance. C.V.Keshav

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March 28, 2009, 08:48		#2
mr_fluent Member MrFluent Join Date: Mar 2009 Posts: 33 Rep Power: 17	take a look at the algo given at our wiki reference. That algorithm works well because i am using it now a days without any problems. In fact my new solver works heavly around it and it performs beautifully. Check your coefficients carefully by printing them, or use this algo to validate small test problem first.

March 29, 2009, 05:37		#3
cvkeshav New Member C.V.Keshav Join Date: Mar 2009 Posts: 2 Rep Power: 0	Hey, I found the error in my code. It is working fine now. Thanks.