Hi! I am looking for block tridiagonal system solver for periodic bc.

can any one refer me a link to download or send me.

my email Id is abdullah_08@yahoo.com

best wishes and thanks

It can be found in numerical recipes in C. Also some parts of the numerical recipes are available online.Just google it.

Harish Thanks for ur response. but i am looking in Fortran, not available n numerical recipes in Fortran.That is why i am looking for another source.

regrads

I think there is also a book "Numerical recipes in fortran" , which is almost the same as this for C. There is what you are looking for in it. Also a university in Italy has put online some fortran programs for this problem. But I don't remember which and can't find the web-site. Hope it helps

Hi Abdullah,

Periodic bc's usually yields "cyclic tridiagonal matrices". In a matrix like that, a value exists on the upper-right corner and another value exists on the lower-left corner of the matrix. They come from the periodicity.

There is a subroutine described in the fortran version of the Numerical Recipies book which is called "cyclic". It also uses subr. "tridiag".

Use both of them together to solve your matrix

you can get these two subroutines via search on the net.Also chapter 2 section 7 of the book above gives explanations that you may need.

ilyas.

Hi Ilyas,

Thank you very much for your response, Yes, i got the idea and also found both subroutines.

any one need them, let me know i can send...

Best wishes Abdullah

yes I need them

Ur email ID...???

sijal2005@gmmail.com