zhpfa
zhpfa - (obsolete) compute the UDU factorization of a Hermitian matrix A in packed storage.
It is typical to follow a call to CHPFA with a call to CHPSL to solve
Ax = b or to CHPDI to compute the determinant, inverse, and inertia of A.
SUBROUTINE ZHPFA( A, N, IPIVOT, INFO)
DOUBLE COMPLEX A(*)
INTEGER N, INFO
INTEGER IPIVOT(*)
SUBROUTINE ZHPFA_64( A, N, IPIVOT, INFO)
DOUBLE COMPLEX A(*)
INTEGER*8 N, INFO
INTEGER*8 IPIVOT(*)
#include <sunperf.h>
void zhpfa(doublecomplex *a, int n, int *ipivot, int *info);
void zhpfa_64(doublecomplex *a, long n, long *ipivot, long *info);
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* A (input/output)
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On entry, the upper triangle of the matrix A.
On exit, a UDU factorization of the matrix A.
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* N (input)
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Order of the matrix A. N >= 0.
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* IPIVOT (output)
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On exit, a vector of pivot indices.
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* INFO (output)
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On exit:
INFO = 0 Subroutine completed normally.
INFO > 0 Returns a value k if the kth pivot block is singular to
indicate that CHPSL or CHPDI will divide by zero if called.