clahef - nite matrix using the Bunch-Kaufman diagonal pivoting method (blocked algorithm, calling Level 3 BLAS)
SUBROUTINE CLAHEF(UPLO, N, NB, KB, A, LDA, IPIV, W, LDW, INFO) CHARACTER*1 UPLO INTEGER INFO, KB, LDA, LDW, N, NB INTEGER IPIV(*) COMPLEX A(LDA,*), W(LDW,*) SUBROUTINE CLAHEF_64(UPLO, N, NB, KB, A, LDA, IPIV, W, LDW, INFO) CHARACTER*1 UPLO INTEGER*8 INFO, KB, LDA, LDW, N, NB INTEGER*8 IPIV(*) COMPLEX A(LDA,*), W(LDW,*) F95 INTERFACE SUBROUTINE LAHEF(UPLO, N, NB, KB, A, LDA, IPIV, W, LDW, INFO) INTEGER :: N, NB, KB, LDA, LDW, INFO CHARACTER(LEN=1) :: UPLO INTEGER, DIMENSION(:) :: IPIV COMPLEX, DIMENSION(:,:) :: A, W SUBROUTINE LAHEF_64(UPLO, N, NB, KB, A, LDA, IPIV, W, LDW, INFO) INTEGER(8) :: N, NB, KB, LDA, LDW, INFO CHARACTER(LEN=1) :: UPLO INTEGER(8), DIMENSION(:) :: IPIV COMPLEX, DIMENSION(:,:) :: A, W C INTERFACE #include <sunperf.h> void clahef (char uplo, int n, int nb, int *kb, floatcomplex *a, int lda, int *ipiv, int ldw, int *info); void clahef_64 (char uplo, long n, long nb, long *kb, floatcomplex *a, long lda, long *ipiv, long ldw, long *info);
Oracle Solaris Studio Performance Library clahef(3P) NAME clahef - compute a partial factorization of a complex Hermitian indefi- nite matrix using the Bunch-Kaufman diagonal pivoting method (blocked algorithm, calling Level 3 BLAS) SYNOPSIS SUBROUTINE CLAHEF(UPLO, N, NB, KB, A, LDA, IPIV, W, LDW, INFO) CHARACTER*1 UPLO INTEGER INFO, KB, LDA, LDW, N, NB INTEGER IPIV(*) COMPLEX A(LDA,*), W(LDW,*) SUBROUTINE CLAHEF_64(UPLO, N, NB, KB, A, LDA, IPIV, W, LDW, INFO) CHARACTER*1 UPLO INTEGER*8 INFO, KB, LDA, LDW, N, NB INTEGER*8 IPIV(*) COMPLEX A(LDA,*), W(LDW,*) F95 INTERFACE SUBROUTINE LAHEF(UPLO, N, NB, KB, A, LDA, IPIV, W, LDW, INFO) INTEGER :: N, NB, KB, LDA, LDW, INFO CHARACTER(LEN=1) :: UPLO INTEGER, DIMENSION(:) :: IPIV COMPLEX, DIMENSION(:,:) :: A, W SUBROUTINE LAHEF_64(UPLO, N, NB, KB, A, LDA, IPIV, W, LDW, INFO) INTEGER(8) :: N, NB, KB, LDA, LDW, INFO CHARACTER(LEN=1) :: UPLO INTEGER(8), DIMENSION(:) :: IPIV COMPLEX, DIMENSION(:,:) :: A, W C INTERFACE #include <sunperf.h> void clahef (char uplo, int n, int nb, int *kb, floatcomplex *a, int lda, int *ipiv, int ldw, int *info); void clahef_64 (char uplo, long n, long nb, long *kb, floatcomplex *a, long lda, long *ipiv, long ldw, long *info); PURPOSE clahef computes a partial factorization of a complex Hermitian matrix A using the Bunch-Kaufman diagonal pivoting method. The partial factor- ization has the form: A = ( I U12 ) ( A11 0 ) ( I 0 ) if UPLO = 'U', or: ( 0 U22 ) ( 0 D ) ( U12**H U22**H ) A = ( L11 0 ) ( D 0 ) ( L11**H L21**H ) if UPLO = 'L' ( L21 I ) ( 0 A22 ) ( 0 I ) where the order of D is at most NB. The actual order is returned in the argument KB, and is either NB or NB-1, or N if N <= NB. Note that U**H denotes the conjugate transpose of U. CLAHEF is an auxiliary routine called by CHETRF. It uses blocked code (calling Level 3 BLAS) to update the submatrix A11 (if UPLO = 'U') or A22 (if UPLO = 'L'). ARGUMENTS UPLO (input) UPLO is CHARACTER*1 Specifies whether the upper or lower triangular part of the Hermitian matrix A is stored: = 'U': Upper triangular = 'L': Lower triangular N (input) N is INTEGER The order of the matrix A. N >= 0. NB (input) NB is INTEGER The maximum number of columns of the matrix A that should be factored. NB should be at least 2 to allow for 2-by-2 pivot blocks. KB (output) KB is INTEGER The number of columns of A that were actually factored. KB is either NB-1 or NB, or N if N <= NB. A (input/output) A is COMPLEX array, dimension (LDA,N) 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, A contains details of the partial factorization. LDA (input) LDA is INTEGER The leading dimension of the array A. LDA >= max(1,N). IPIV (output) IPIV is INTEGER array, dimension (N) Details of the interchanges and the block structure of D. If UPLO = 'U', only the last KB elements of IPIV are set; if UPLO = 'L', only the first KB elements are set. If IPIV(k) > 0, then rows and columns k and IPIV(k) were interchanged and D(k,k) is a 1-by-1 diagonal block. If UPLO = 'U' and IPIV(k) = IPIV(k-1) < 0, then rows and col- umns k-1 and -IPIV(k) were interchanged and D(k-1:k,k-1:k) is a 2-by-2 diagonal block. If UPLO = 'L' and IPIV(k) = IPIV(k+1) < 0, then rows and columns k+1 and -IPIV(k) were interchanged and D(k:k+1,k:k+1) is a 2-by-2 diagonal block. W (output) W is COMPLEX array, dimension (LDW,NB) LDW (input) LDW is INTEGER The leading dimension of the array W. LDW >= max(1,N). INFO (output) INFO is INTEGER = 0: successful exit, > 0: if INFO = k, D(k,k) is exactly zero. The factorization has been completed, but the block diagonal matrix D is exactly singular. 7 Nov 2015 clahef(3P)