chpdi
chpdi - (obsolete) compute the determinant, inertia, and inverse of a Hermitian matrix A in
packed storage, which has been UDU-factored by CHPCO or CHPFA.
SUBROUTINE CHPDI( A, N, IPIVOT, DET, INERT, WORK, JOB)
COMPLEX A(*), WORK(*)
INTEGER N, JOB
INTEGER IPIVOT(*), INERT(*)
REAL DET(*)
SUBROUTINE CHPDI_64( A, N, IPIVOT, DET, INERT, WORK, JOB)
COMPLEX A(*), WORK(*)
INTEGER*8 N, JOB
INTEGER*8 IPIVOT(*), INERT(*)
REAL DET(*)
#include <sunperf.h>
void chpdi(complex *a, int n, int *ipivot, float *det, int *inert, int job);
void chpdi_64(complex *a, long n, long *ipivot, float *det, long *inert, long job);
-
* A (input/output)
-
On entry, the UDU factorization of the matrix, as computed by
CHPCO or CHPFA.
On exit, if the c digit of JOB <> 0, then A contains the upper triangle
of the inverse of the original matrix A; otherwise unchanged.
-
* N (input)
-
Order of the original matrix A. N >= 0.
-
* IPIVOT (input)
-
Pivot vector as computed by CHPCO or CHPFA.
-
* DET (output)
-
On exit, if the b digit of JOB <> 0, then DET contains the
determinant of the matrix A. The determinant
is stored as b * (10 ** expon) where b is stored in DET(1) and
expon is stored in DET(2). 1.0 <= |DET(1)| <= 10.0 or DET(1) = 0.0. If
the b digit of JOB = 0, DET is not referenced.
-
* INERT (output)
-
On exit, if the a digit of JOB <> 0, then INERT contains an
integer triplet where:
INERT(1) = number of positive eigenvalues
INERT(2) = number of negative eigenvalues
INERT(3) = number of zero eigenvalues
If the a digit of JOB = 0 then INERT is not referenced.
-
* WORK (workspace)
-
Scratch array with a dimension of N.
-
* JOB (input)
-
Integer in the form abc; determines operation subroutine will perform:
a <> 0 Compute the inertia.
b <> 0 Compute the determinant.
c <> 0 Compute the inverse.