chpgst (3p)

Name

chpgst - definite generalized eigenproblem to standard form, using packed storage

Synopsis

SUBROUTINE CHPGST(ITYPE, UPLO, N, AP, BP, INFO)

CHARACTER*1 UPLO
COMPLEX AP(*), BP(*)
INTEGER ITYPE, N, INFO

SUBROUTINE CHPGST_64(ITYPE, UPLO, N, AP, BP, INFO)

CHARACTER*1 UPLO
COMPLEX AP(*), BP(*)
INTEGER*8 ITYPE, N, INFO




F95 INTERFACE
SUBROUTINE HPGST(ITYPE, UPLO, N, AP, BP, INFO)

CHARACTER(LEN=1) :: UPLO
COMPLEX, DIMENSION(:) :: AP, BP
INTEGER :: ITYPE, N, INFO

SUBROUTINE HPGST_64(ITYPE, UPLO, N, AP, BP, INFO)

CHARACTER(LEN=1) :: UPLO
COMPLEX, DIMENSION(:) :: AP, BP
INTEGER(8) :: ITYPE, N, INFO




C INTERFACE
#include <sunperf.h>

void chpgst(int itype, char uplo, int n, complex *ap, complex *bp,  int
*info);

void chpgst_64(long itype, char uplo, long n, complex *ap, complex *bp,
long *info);

Description

Oracle Solaris Studio Performance Library                           chpgst(3P)



NAME
       chpgst  -  reduce a complex Hermitian-definite generalized eigenproblem
       to standard form, using packed storage


SYNOPSIS
       SUBROUTINE CHPGST(ITYPE, UPLO, N, AP, BP, INFO)

       CHARACTER*1 UPLO
       COMPLEX AP(*), BP(*)
       INTEGER ITYPE, N, INFO

       SUBROUTINE CHPGST_64(ITYPE, UPLO, N, AP, BP, INFO)

       CHARACTER*1 UPLO
       COMPLEX AP(*), BP(*)
       INTEGER*8 ITYPE, N, INFO




   F95 INTERFACE
       SUBROUTINE HPGST(ITYPE, UPLO, N, AP, BP, INFO)

       CHARACTER(LEN=1) :: UPLO
       COMPLEX, DIMENSION(:) :: AP, BP
       INTEGER :: ITYPE, N, INFO

       SUBROUTINE HPGST_64(ITYPE, UPLO, N, AP, BP, INFO)

       CHARACTER(LEN=1) :: UPLO
       COMPLEX, DIMENSION(:) :: AP, BP
       INTEGER(8) :: ITYPE, N, INFO




   C INTERFACE
       #include <sunperf.h>

       void chpgst(int itype, char uplo, int n, complex *ap, complex *bp,  int
                 *info);

       void chpgst_64(long itype, char uplo, long n, complex *ap, complex *bp,
                 long *info);



PURPOSE
       chpgst reduces a complex Hermitian-definite generalized eigenproblem to
       standard form, using packed storage.

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

       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**H or L**H*A*L.

       B must have been previously factorized as U**H*U or L*L**H by CPPTRF.


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


       UPLO (input)
                 =  'U':   Upper  triangle of A is stored and B is factored as
                 U**H*U; = 'L':  Lower triangle of A is stored and B  is  fac-
                 tored as L*L**H.


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


       AP (input/output) COMPLEX array, dimension (N*(N+1)/2)
                 On entry, the upper or lower triangle of the Hermitian matrix
                 A, packed columnwise in a linear array.  The j-th column of A
                 is  stored  in the array AP as follows: if UPLO = 'U', AP(i +
                 (j-1)*j/2) = A(i,j) for  1<=i<=j;  if  UPLO  =  'L',  AP(i  +
                 (j-1)*(2n-j)/2) = A(i,j) for j<=i<=n.

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


       BP (input) COMPLEX array, dimension (N*(N+1)/2)
                 The triangular factor from the Cholesky factorization  of  B,
                 stored in the same format as A, as returned by CPPTRF.


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




                                  7 Nov 2015                        chpgst(3P)