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SUBROUTINE SGEDI (A,LDA,N,IPVT,DET,WORK,JOB) C$ (Solve for Determinant and Inverse) 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 C$ contains a zero on the diagonal and the inverse is C$ requested. It will not occur if the subroutines are C$ called correctly and if SGECO has set RCOND .GT. 0.0 C$ or SGEFA has set 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$ (03-APR-82)