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 A.M.Yang February 26, 2001 23:27

Periodic Block Tridiagonl System

Hi, Can you tell me where I can get the knowledge of the solution of Periodic Block Tridiagonl System of equations? Thank you!

A.M.Yang

02/27/01

 sylvain February 27, 2001 05:11

Re: Periodic Block Tridiagonl System

www.nr.com

you should find something there.

 M. Barbaro February 27, 2001 06:07

Re: Periodic Block Tridiagonl System

Try this book:

Anderson, Tannehill, Pletcher COMPUTATIONAL FLUID MECHANICS AND HEAT TRANSFER, Hemisphere Publishing Corporation(1984),p.551

Regards

 A.M.Yang February 27, 2001 08:26

Re: Periodic Block Tridiagonl System

Dear Mr.Barbaro,M:

Thank you for your advice. The Book of Anderson is at my hand, but the program seems erroneous.

Regards

A.M.Yang

02/27/2001

 A.M.Yang February 27, 2001 08:28

Thank You!

Dear Mr. Sylvain:

Regards

A.M.Yang

02/27/2001

 andy February 27, 2001 10:59

Re: Periodic Block Tridiagonl System

I had the same problem a few years ago. It was not in my copy of Numerical Recipes (1986) but may be in a newer version (?). An approach is as follows (I never found a reference):

Write down the matrix problem. Pull out the last equation for Xn to leave a tridiagonal system. Split the unknown x into the sum of two parts: x = f + Xn*g. Solve two TDMA problems for f and g (g gets the Xn*A terms to divide out Xn and the f the rest). Use Xn equation to get Xn. Evaluate x from f and g.

 A.M.Yang February 27, 2001 23:22

Re: Periodic Block Tridiagonl System

Dear Andy:

Regards

A.M.Yang

 A.M.Yang February 28, 2001 22:46

Re: Periodic Block Tridiagonl System

Dear Andy:

Can you give me the process in detail?

Thank you very much!

Regards

A.M.Yang

(aimingyang@263.net)

 andy March 1, 2001 07:31

Re: Periodic Block Tridiagonl System

A reference has been pointed out to me. Fortran code is contained in an appendix of Volume 1 of Hirsch's book. My original source was a proprietary routine from the 1970s. They have coding similarities which suggests it is in a numerical library somewhere or, perhaps, it is just one of those routines that has been passed among Ph.D. students since the dawn of time. Digging about on netlib is likely to be fruitful. However, I had missed the word "block" on the first reading of your question so it may not be want you want anyway.

 A.M.Yang March 1, 2001 09:26

Re: Periodic Block Tridiagonl System

Dear Andy:

Thank you very much !

Regards

A.M.Yang

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