CPODI(3F)CPODI(3F)NAMECPODI - CPODI computes the determinant and inverse of a certain complex
Hermitian positive definite matrix (see below) using the factors computed
by CPOCO, CPOFA or CQRDC.
SYNOPSYS
SUBROUTINE CPODI(A,LDA,N,DET,JOB)
DESCRIPTION
On Entry
A COMPLEX(LDA, N)
the output A from CPOCO or CPOFA
or the output X from CQRDC.
LDA INTEGER
the leading dimension of the array A .
N INTEGER
the order of the matrix A .
JOB INTEGER
= 11 both determinant and inverse.
= 01 inverse only.
= 10 determinant only. On Return
A If CPOCO or CPOFA was used to factor A then
CPODI produces the upper half of INVERSE(A) .
If CQRDC was used to decompose X then
CPODI produces the upper half of INVERSE(CTRANS(X)*X)
where CTRANS(X) is the conjugate transpose.
Elements of A below the diagonal are unchanged.
If the units digit of JOB is zero, A is unchanged.
DET REAL(2)
determinant of A or of CTRANS(X)*X if requested.
Otherwise not referenced.
Determinant = DET(1) * 10.0**DET(2)
with 1.0 .LE. 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 CPOCO or CPOFA 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 CAXPY,CSCAL Fortran CONJG,MOD,REAL
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