DGEDI(3F)DGEDI(3F)NAMEDGEDI - DGEDI computes the determinant and inverse of a matrix using
the factors computed by DGECO or DGEFA.
SYNOPSYS
SUBROUTINE DGEDI(A,LDA,N,IPVT,DET,WORK,JOB)
DESCRIPTION
On Entry
A DOUBLE PRECISION(LDA, N)
the output from DGECO or DGEFA.
LDA INTEGER
the leading dimension of the array A .
N INTEGER
the order of the matrix A .
IPVT INTEGER(N)
the pivot vector from DGECO or DGEFA.
WORK DOUBLE PRECISION(N)
work vector. Contents destroyed.
JOB INTEGER
= 11 both determinant and inverse.
= 01 inverse only.
= 10 determinant only. On Return
A inverse of original matrix if requested.
Otherwise unchanged.
DET DOUBLE PRECISION(2)
determinant of original matrix if requested.
Otherwise not referenced.
Determinant = DET(1) * 10.0**DET(2)
with 1.0 .LE. DABS(DET(1)) .LT. 10.0
or DET(1) .EQ. 0.0 . Error Condition
A division by zero will occur if the input factor contains a zero on the
diagonal and the inverse is requested. It will not occur if the
subroutines are called correctly and if DGECO has set RCOND .GT. 0.0 or
DGEFA has set INFO .EQ. 0 . LINPACK. This version dated 08/14/78 .
Cleve Moler, University of New Mexico, Argonne National Lab. Subroutines
and Functions BLAS DAXPY,DSCAL,DSWAP Fortran DABS,MOD
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