dgedi.f
SUBROUTINE DGEDI (A, LDA, N, IPVT, DET, WORK, JOB)
C***BEGIN PROLOGUE DGEDI
C***PURPOSE Compute the determinant and inverse of a matrix using the
C factors computed by DGECO or DGEFA.
C***LIBRARY SLATEC (LINPACK)
C***CATEGORY D3A1, D2A1
C***TYPE DOUBLE PRECISION (SGEDI-S, DGEDI-D, CGEDI-C)
C***KEYWORDS DETERMINANT, INVERSE, LINEAR ALGEBRA, LINPACK, MATRIX
C***AUTHOR Moler, C. B., (U. of New Mexico)
C***DESCRIPTION
C
C DGEDI computes the determinant and inverse of a matrix
C using the factors computed by DGECO or DGEFA.
C
C On Entry
C
C A DOUBLE PRECISION(LDA, N)
C the output from DGECO or DGEFA.
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 DGECO or DGEFA.
C
C WORK DOUBLE PRECISION(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 DOUBLE PRECISION(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 DGECO has set RCOND .GT. 0.0 or DGEFA has set
C INFO .EQ. 0 .
C
C***REFERENCES J. J. Dongarra, J. R. Bunch, C. B. Moler, and G. W.
C Stewart, LINPACK Users' Guide, SIAM, 1979.
C***ROUTINES CALLED DAXPY, DSCAL, DSWAP
C***REVISION HISTORY (YYMMDD)
C 780814 DATE WRITTEN
C 890531 Changed all specific intrinsics to generic. (WRB)
C 890831 Modified array declarations. (WRB)
C 890831 REVISION DATE from Version 3.2
C 891214 Prologue converted to Version 4.0 format. (BAB)
C 900326 Removed duplicate information from DESCRIPTION section.
C (WRB)
C 920501 Reformatted the REFERENCES section. (WRB)
C***END PROLOGUE DGEDI