zungtr - generate a complex unitary matrix Q which is defined as the product of n-1 elementary reflectors of order N, as returned by CHETRD
SUBROUTINE ZUNGTR(UPLO, N, A, LDA, TAU, WORK, LWORK, INFO) CHARACTER*1 UPLO DOUBLE COMPLEX A(LDA,*), TAU(*), WORK(*) INTEGER N, LDA, LWORK, INFO SUBROUTINE ZUNGTR_64(UPLO, N, A, LDA, TAU, WORK, LWORK, INFO) CHARACTER*1 UPLO DOUBLE COMPLEX A(LDA,*), TAU(*), WORK(*) INTEGER*8 N, LDA, LWORK, INFO F95 INTERFACE SUBROUTINE UNGTR(UPLO, N, A, LDA, TAU, WORK, LWORK, INFO) CHARACTER(LEN=1) :: UPLO COMPLEX(8), DIMENSION(:) :: TAU, WORK COMPLEX(8), DIMENSION(:,:) :: A INTEGER :: N, LDA, LWORK, INFO SUBROUTINE UNGTR_64(UPLO, N, A, LDA, TAU, WORK, LWORK, INFO) CHARACTER(LEN=1) :: UPLO COMPLEX(8), DIMENSION(:) :: TAU, WORK COMPLEX(8), DIMENSION(:,:) :: A INTEGER(8) :: N, LDA, LWORK, INFO C INTERFACE #include <sunperf.h> void zungtr(char uplo, int n, doublecomplex *a, int lda, doublecomplex *tau, int *info); void zungtr_64(char uplo, long n, doublecomplex *a, long lda, double- complex *tau, long *info);
Oracle Solaris Studio Performance Library zungtr(3P) NAME zungtr - generate a complex unitary matrix Q which is defined as the product of n-1 elementary reflectors of order N, as returned by CHETRD SYNOPSIS SUBROUTINE ZUNGTR(UPLO, N, A, LDA, TAU, WORK, LWORK, INFO) CHARACTER*1 UPLO DOUBLE COMPLEX A(LDA,*), TAU(*), WORK(*) INTEGER N, LDA, LWORK, INFO SUBROUTINE ZUNGTR_64(UPLO, N, A, LDA, TAU, WORK, LWORK, INFO) CHARACTER*1 UPLO DOUBLE COMPLEX A(LDA,*), TAU(*), WORK(*) INTEGER*8 N, LDA, LWORK, INFO F95 INTERFACE SUBROUTINE UNGTR(UPLO, N, A, LDA, TAU, WORK, LWORK, INFO) CHARACTER(LEN=1) :: UPLO COMPLEX(8), DIMENSION(:) :: TAU, WORK COMPLEX(8), DIMENSION(:,:) :: A INTEGER :: N, LDA, LWORK, INFO SUBROUTINE UNGTR_64(UPLO, N, A, LDA, TAU, WORK, LWORK, INFO) CHARACTER(LEN=1) :: UPLO COMPLEX(8), DIMENSION(:) :: TAU, WORK COMPLEX(8), DIMENSION(:,:) :: A INTEGER(8) :: N, LDA, LWORK, INFO C INTERFACE #include <sunperf.h> void zungtr(char uplo, int n, doublecomplex *a, int lda, doublecomplex *tau, int *info); void zungtr_64(char uplo, long n, doublecomplex *a, long lda, double- complex *tau, long *info); PURPOSE zungtr generates a complex unitary matrix Q which is defined as the product of n-1 elementary reflectors of order N, as returned by CHETRD: if UPLO = 'U', Q = H(n-1) . . . H(2) H(1), if UPLO = 'L', Q = H(1) H(2) . . . H(n-1). ARGUMENTS UPLO (input) = 'U': Upper triangle of A contains elementary reflectors from CHETRD; = 'L': Lower triangle of A contains elementary reflectors from CHETRD. N (input) The order of the matrix Q. N >= 0. A (input/output) On entry, the vectors which define the elementary reflectors, as returned by CHETRD. On exit, the N-by-N unitary matrix Q. LDA (input) The leading dimension of the array A. LDA >= N. TAU (input) TAU(i) must contain the scalar factor of the elementary reflector H(i), as returned by CHETRD. WORK (workspace) On exit, if INFO = 0, WORK(1) returns the optimal LWORK. LWORK (input) The dimension of the array WORK. LWORK >= N-1. For optimum performance LWORK >= (N-1)*NB, where NB is the optimal block- size. If LWORK = -1, then a workspace query is assumed; the routine only calculates the optimal size of the WORK array, returns this value as the first entry of the WORK array, and no error message related to LWORK is issued by XERBLA. INFO (output) = 0: successful exit; < 0: if INFO = -i, the i-th argument had an illegal value. 7 Nov 2015 zungtr(3P)