looking for a subroutine

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Hi C++ Forum,

I've been trying to find a subroutine to find the eigenvectors and eigenvalues of a tridiagonal matrix. More specifically, the Jacobi method or the QR method. So far though, I have found about 3 or 4 both Jacobi and QR all written in C. Though I have been told that it is relatively easy to translate the code into C++, I'm wondering if anyone knows where I can find a Jacobi/QR C++ subroutine....

I am using Visual Studio.

cheers and thanks for any help given.

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