This example computes all the eigenvalues of $Az=\lambda Bz$, where Here $A$ is symmetric, $B$ is symmetric positive definite, and $A$ and $B$ are treated as band matrices. $B$ must first be factorized by dpbstf. The program calls dsbgst to reduce the problem to the standard form $Cy=\lambda y$, then dsbtrd to reduce $C$ to tridiagonal form, and dsterf to compute the eigenvalues.