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SSISL

       SUBROUTINE SSISL(A,LDA,N,KPVT,B)
       INTEGER LDA,N,KPVT(1)
       REAL A(LDA,1),B(1)
 C
 C     SSISL SOLVES THE REAL SYMMETRIC SYSTEM
 C     A * X = B
 C     USING THE FACTORS COMPUTED BY SSIFA.
 C
 C     ON ENTRY
 C
 C        A       REAL(LDA,N)
 C                THE OUTPUT FROM SSIFA.
 C
 C        LDA     INTEGER
 C                THE LEADING DIMENSION OF THE ARRAY  A .
 C
 C        N       INTEGER
 C                THE ORDER OF THE MATRIX  A .
 C
 C        KPVT    INTEGER(N)
 C                THE PIVOT VECTOR FROM SSIFA.
 C
 C        B       REAL(N)
 C                THE RIGHT HAND SIDE VECTOR.
 C
 C     ON RETURN
 C
 C        B       THE SOLUTION VECTOR  X .
 C
 C     ERROR CONDITION
 C
 C        A DIVISION BY ZERO MAY OCCUR IF  SSICO  HAS SET RCOND .EQ. 0
 C        OR  SSIFA  HAS SET INFO .NE. 0  .
 C
 C     TO COMPUTE  INVERSE(A) * C  WHERE  C  IS A MATRIX
 C     WITH  P  COLUMNS
 C           CALL SSIFA(A,LDA,N,KPVT,INFO)
 C           IF (INFO .NE. 0) GO TO ...
 C           DO 10 J = 1, P
 C              CALL SSISL(A,LDA,N,KPVT,C(1,J))
 C        10 CONTINUE
 C
 C     LINPACK. THIS VERSION DATED 08/14/78 .
 C     JAMES BUNCH, UNIV. CALIF. SAN DIEGO, ARGONNE NAT. LAB.
 C
 C     SUBROUTINES AND FUNCTIONS
 C
 C     BLAS SAXPY,SDOT
 C     FORTRAN IABS
 C