zhegs2 (3p)

Name

zhegs2 - definite generalized eigenproblem to standard form

Synopsis

SUBROUTINE ZHEGS2(ITYPE, UPLO, N, A, LDA, B, LDB, INFO)

CHARACTER*1 UPLO
DOUBLE COMPLEX A(LDA,*), B(LDB,*)
INTEGER ITYPE, N, LDA, LDB, INFO

SUBROUTINE ZHEGS2_64(ITYPE, UPLO, N, A, LDA, B, LDB, INFO)

CHARACTER*1 UPLO
DOUBLE COMPLEX A(LDA,*), B(LDB,*)
INTEGER*8 ITYPE, N, LDA, LDB, INFO




F95 INTERFACE
SUBROUTINE HEGS2(ITYPE, UPLO, N, A, LDA, B, LDB, INFO)

CHARACTER(LEN=1) :: UPLO
COMPLEX(8), DIMENSION(:,:) :: A, B
INTEGER :: ITYPE, N, LDA, LDB, INFO

SUBROUTINE HEGS2_64(ITYPE, UPLO, N, A, LDA, B, LDB, INFO)

CHARACTER(LEN=1) :: UPLO
COMPLEX(8), DIMENSION(:,:) :: A, B
INTEGER(8) :: ITYPE, N, LDA, LDB, INFO




C INTERFACE
#include <sunperf.h>

void zhegs2(int itype, char uplo, int n,  doublecomplex  *a,  int  lda,
doublecomplex *b, int ldb, int *info);

void  zhegs2_64(long  itype,  char uplo, long n, doublecomplex *a, long
lda, doublecomplex *b, long ldb, long *info);

Description

Oracle Solaris Studio Performance Library                           zhegs2(3P)



NAME
       zhegs2  -  reduce a complex Hermitian-definite generalized eigenproblem
       to standard form


SYNOPSIS
       SUBROUTINE ZHEGS2(ITYPE, UPLO, N, A, LDA, B, LDB, INFO)

       CHARACTER*1 UPLO
       DOUBLE COMPLEX A(LDA,*), B(LDB,*)
       INTEGER ITYPE, N, LDA, LDB, INFO

       SUBROUTINE ZHEGS2_64(ITYPE, UPLO, N, A, LDA, B, LDB, INFO)

       CHARACTER*1 UPLO
       DOUBLE COMPLEX A(LDA,*), B(LDB,*)
       INTEGER*8 ITYPE, N, LDA, LDB, INFO




   F95 INTERFACE
       SUBROUTINE HEGS2(ITYPE, UPLO, N, A, LDA, B, LDB, INFO)

       CHARACTER(LEN=1) :: UPLO
       COMPLEX(8), DIMENSION(:,:) :: A, B
       INTEGER :: ITYPE, N, LDA, LDB, INFO

       SUBROUTINE HEGS2_64(ITYPE, UPLO, N, A, LDA, B, LDB, INFO)

       CHARACTER(LEN=1) :: UPLO
       COMPLEX(8), DIMENSION(:,:) :: A, B
       INTEGER(8) :: ITYPE, N, LDA, LDB, INFO




   C INTERFACE
       #include <sunperf.h>

       void zhegs2(int itype, char uplo, int n,  doublecomplex  *a,  int  lda,
                 doublecomplex *b, int ldb, int *info);

       void  zhegs2_64(long  itype,  char uplo, long n, doublecomplex *a, long
                 lda, doublecomplex *b, long ldb, long *info);



PURPOSE
       zhegs2 reduces a complex Hermitian-definite generalized eigenproblem to
       standard form.

       If ITYPE = 1, the problem is A*x = lambda*B*x,
       and A is overwritten by inv(U')*A*inv(U) or inv(L)*A*inv(L')

       If ITYPE = 2 or 3, the problem is A*B*x = lambda*x or
       B*A*x = lambda*x, and A is overwritten by U*A*U` or L'*A*L.

       B must have been previously factorized as U'*U or L*L' by CPOTRF.


ARGUMENTS
       ITYPE (input)
                 = 1: compute inv(U')*A*inv(U) or inv(L)*A*inv(L');
                 = 2 or 3: compute U*A*U' or L'*A*L.


       UPLO (input)
                 Specifies  whether  the upper or lower triangular part of the
                 Hermitian matrix A is stored, and how B has been  factorized.
                 = 'U':  Upper triangular
                 = 'L':  Lower triangular


       N (input) The order of the matrices A and B.  N >= 0.


       A (input/output)
                 On entry, the Hermitian matrix A.  If UPLO = 'U', the leading
                 n by n upper triangular part of A contains the upper triangu-
                 lar  part  of the matrix A, and the strictly lower triangular
                 part of A is not referenced.  If UPLO = 'L', the leading n by
                 n  lower  triangular  part of A contains the lower triangular
                 part of the matrix A, and the strictly upper triangular  part
                 of A is not referenced.

                 On  exit,  if INFO = 0, the transformed matrix, stored in the
                 same format as A.


       LDA (input)
                 The leading dimension of the array A.  LDA >= max(1,N).


       B (input) The triangular factor from the Cholesky factorization  of  B,
                 as returned by CPOTRF.


       LDB (input)
                 The leading dimension of the array B.  LDB >= max(1,N).


       INFO (output)
                 = 0:  successful exit.
                 < 0:  if INFO = -i, the i-th argument had an illegal value.




                                  7 Nov 2015                        zhegs2(3P)