SUBROUTINE CGGHRD( COMPQ, COMPZ, N, ILO, IHI, A, LDA, B, LDB, Q, * LDQ, Z, LDZ, INFO) CHARACTER * 1 COMPQ, COMPZ COMPLEX A(LDA,*), B(LDB,*), Q(LDQ,*), Z(LDZ,*) INTEGER N, ILO, IHI, LDA, LDB, LDQ, LDZ, INFO SUBROUTINE CGGHRD_64( COMPQ, COMPZ, N, ILO, IHI, A, LDA, B, LDB, Q, * LDQ, Z, LDZ, INFO) CHARACTER * 1 COMPQ, COMPZ COMPLEX A(LDA,*), B(LDB,*), Q(LDQ,*), Z(LDZ,*) INTEGER*8 N, ILO, IHI, LDA, LDB, LDQ, LDZ, INFO
SUBROUTINE GGHRD( COMPQ, COMPZ, [N], ILO, IHI, A, [LDA], B, [LDB], * Q, [LDQ], Z, [LDZ], [INFO]) CHARACTER(LEN=1) :: COMPQ, COMPZ COMPLEX, DIMENSION(:,:) :: A, B, Q, Z INTEGER :: N, ILO, IHI, LDA, LDB, LDQ, LDZ, INFO SUBROUTINE GGHRD_64( COMPQ, COMPZ, [N], ILO, IHI, A, [LDA], B, [LDB], * Q, [LDQ], Z, [LDZ], [INFO]) CHARACTER(LEN=1) :: COMPQ, COMPZ COMPLEX, DIMENSION(:,:) :: A, B, Q, Z INTEGER(8) :: N, ILO, IHI, LDA, LDB, LDQ, LDZ, INFO
void cgghrd(char compq, char compz, int n, int ilo, int ihi, complex *a, int lda, complex *b, int ldb, complex *q, int ldq, complex *z, int ldz, int *info);
void cgghrd_64(char compq, char compz, long n, long ilo, long ihi, complex *a, long lda, complex *b, long ldb, complex *q, long ldq, complex *z, long ldz, long *info);
The unitary matrices Q and Z are determined as products of Givens rotations. They may either be formed explicitly, or they may be postmultiplied into input matrices Q1 and Z1, so that
1 * A * Z1' = (Q1*Q) * H * (Z1*Z)' 1 * B * Z1' = (Q1*Q) * T * (Z1*Z)'
If COMPQ='I': on entry, Q need not be set, and on exit it contains the unitary matrix Q, where Q' is the product of the Givens transformations which are applied to A and B on the left. If COMPQ='V': on entry, Q must contain a unitary matrix Q1, and on exit this is overwritten by Q1*Q.
If COMPZ='I': on entry, Z need not be set, and on exit it contains the unitary matrix Z, which is the product of the Givens transformations which are applied to A and B on the right. If COMPZ='V': on entry, Z must contain a unitary matrix Z1, and on exit this is overwritten by Z1*Z.