      SUBROUTINE SGEDI(A,LDA,N,IPVT,DET,WORK,JOB)
      INTEGER LDA,N,IPVT(*),JOB
      REAL A(LDA,*),DET(2),WORK(*)
C
C     SGEDI COMPUTES THE DETERMINANT AND INVERSE OF A MATRIX
C     USING THE FACTORS COMPUTED BY SGECO OR SGEFA.
C
C     ON ENTRY
C
C        A       REAL(LDA, N)
C                THE OUTPUT FROM SGECO OR SGEFA.
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        IPVT    INTEGER(N)
C                THE PIVOT VECTOR FROM SGECO OR SGEFA.
C
C        WORK    REAL(N)
C                WORK VECTOR.  CONTENTS DESTROYED.
C
C        JOB     INTEGER
C                = 11   BOTH DETERMINANT AND INVERSE.
C                = 01   INVERSE ONLY.
C                = 10   DETERMINANT ONLY.
C
C     ON RETURN
C
C        A       INVERSE OF ORIGINAL MATRIX IF REQUESTED.
C                OTHERWISE UNCHANGED.
C
C        DET     REAL(2)
C                DETERMINANT OF ORIGINAL MATRIX IF REQUESTED.
C                OTHERWISE NOT REFERENCED.
C                DETERMINANT = DET(1) * 10.0**DET(2)
C                WITH  1.0 .LE. ABS(DET(1)) .LT. 10.0
C                OR  DET(1) .EQ. 0.0 .
C
C     ERROR CONDITION
C
C        A DIVISION BY ZERO WILL OCCUR IF THE INPUT FACTOR CONTAINS
C        A ZERO ON THE DIAGONAL AND THE INVERSE IS REQUESTED.
C        IT WILL NOT OCCUR IF THE SUBROUTINES ARE CALLED CORRECTLY
C        AND IF SGECO HAS SET RCOND .GT. 0.0 OR SGEFA HAS SET
C        INFO .EQ. 0 .
C
C     LINPACK. THIS VERSION DATED 08/14/78 .
C     CLEVE MOLER, UNIVERSITY OF NEW MEXICO, ARGONNE NATIONAL LAB.
C
C     SUBROUTINES AND FUNCTIONS
C
C     BLAS SAXPY,SSCAL,SSWAP
C     FORTRAN ABS,MOD
C
C     INTERNAL VARIABLES
C
      REAL T
      REAL TEN
      INTEGER I,J,K,KB,KP1,L,NM1
C
C
C     COMPUTE DETERMINANT
C
      IF (JOB/10 .EQ. 0) GO TO 70
         DET(1) = 1.0E0
         DET(2) = 0.0E0
         TEN = 10.0E0
         DO 50 I = 1, N
            IF (IPVT(I) .NE. I) DET(1) = -DET(1)
            DET(1) = A(I,I)*DET(1)
C        ...EXIT
            IF (DET(1) .EQ. 0.0E0) GO TO 60
   10       IF (ABS(DET(1)) .GE. 1.0E0) GO TO 20
               DET(1) = TEN*DET(1)
               DET(2) = DET(2) - 1.0E0
            GO TO 10
   20       CONTINUE
   30       IF (ABS(DET(1)) .LT. TEN) GO TO 40
               DET(1) = DET(1)/TEN
               DET(2) = DET(2) + 1.0E0
            GO TO 30
   40       CONTINUE
   50    CONTINUE
   60    CONTINUE
   70 CONTINUE
C
C     COMPUTE INVERSE(U)
C
      IF (MOD(JOB,10) .EQ. 0) GO TO 150
         DO 100 K = 1, N
            A(K,K) = 1.0E0/A(K,K)
            T = -A(K,K)
            CALL SSCAL(K-1,T,A(1,K),1)
            KP1 = K + 1
            IF (N .LT. KP1) GO TO 90
            DO 80 J = KP1, N
               T = A(K,J)
               A(K,J) = 0.0E0
               CALL SAXPY(K,T,A(1,K),1,A(1,J),1)
   80       CONTINUE
   90       CONTINUE
  100    CONTINUE
C
C        FORM INVERSE(U)*INVERSE(L)
C
         NM1 = N - 1
         IF (NM1 .LT. 1) GO TO 140
         DO 130 KB = 1, NM1
            K = N - KB
            KP1 = K + 1
            DO 110 I = KP1, N
               WORK(I) = A(I,K)
               A(I,K) = 0.0E0
  110       CONTINUE
            DO 120 J = KP1, N
               T = WORK(J)
               CALL SAXPY(N,T,A(1,J),1,A(1,K),1)
  120       CONTINUE
            L = IPVT(K)
            IF (L .NE. K) CALL SSWAP(N,A(1,K),1,A(1,L),1)
  130    CONTINUE
  140    CONTINUE
  150 CONTINUE
      RETURN
      END
