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SGTSL

       SUBROUTINE SGTSL(N,C,D,E,B,INFO)
       INTEGER N,INFO
       REAL C(1),D(1),E(1),B(1)
 C
 C     SGTSL GIVEN A GENERAL TRIDIAGONAL MATRIX AND A RIGHT HAND
 C     SIDE WILL FIND THE SOLUTION.
 C
 C     ON ENTRY
 C
 C        N       INTEGER
 C                IS THE ORDER OF THE TRIDIAGONAL MATRIX.
 C
 C        C       REAL(N)
 C                IS THE SUBDIAGONAL OF THE TRIDIAGONAL MATRIX.
 C                C(2) THROUGH C(N) SHOULD CONTAIN THE SUBDIAGONAL.
 C                ON OUTPUT C IS DESTROYED.
 C
 C        D       REAL(N)
 C                IS THE DIAGONAL OF THE TRIDIAGONAL MATRIX.
 C                ON OUTPUT D IS DESTROYED.
 C
 C        E       REAL(N)
 C                IS THE SUPERDIAGONAL OF THE TRIDIAGONAL MATRIX.
 C                E(1) THROUGH E(N-1) SHOULD CONTAIN THE SUPERDIAGONAL
 C                ON OUTPUT E IS DESTROYED.
 C
 C        B       REAL(N)
 C                IS THE RIGHT HAND SIDE VECTOR.
 C
 C     ON RETURN
 C
 C        B       IS THE SOLUTION VECTOR.
 C
 C        INFO    INTEGER
 C                = 0 NORMAL VALUE.
 C                = K IF THE K-TH ELEMENT OF THE DIAGONAL BECOMES
 C                    EXACTLY ZERO.  THE SUBROUTINE RETURNS WHEN
 C                    THIS IS DETECTED.
 C
 C     LINPACK. THIS VERSION DATED 08/14/78 .
 C     JACK DONGARRA, ARGONNE NATIONAL LABORATORY.
 C
 C     NO EXTERNALS
 C     FORTRAN ABS
 C