CPODI(3F)
CPODI - 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.
As shipped in IRIX 6.5.19. Unchanged since IRIX 6.5.
NAME CPODI - 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