SUBROUTINE CHEEVD( JOBZ, UPLO, N, A, LDA, W, WORK, LWORK, RWORK, * LRWORK, IWORK, LIWORK, INFO) CHARACTER * 1 JOBZ, UPLO COMPLEX A(LDA,*), WORK(*) INTEGER N, LDA, LWORK, LRWORK, LIWORK, INFO INTEGER IWORK(*) REAL W(*), RWORK(*) SUBROUTINE CHEEVD_64( JOBZ, UPLO, N, A, LDA, W, WORK, LWORK, RWORK, * LRWORK, IWORK, LIWORK, INFO) CHARACTER * 1 JOBZ, UPLO COMPLEX A(LDA,*), WORK(*) INTEGER*8 N, LDA, LWORK, LRWORK, LIWORK, INFO INTEGER*8 IWORK(*) REAL W(*), RWORK(*)
SUBROUTINE HEEVD( JOBZ, UPLO, [N], A, [LDA], W, [WORK], [LWORK], * [RWORK], [LRWORK], [IWORK], [LIWORK], [INFO]) CHARACTER(LEN=1) :: JOBZ, UPLO COMPLEX, DIMENSION(:) :: WORK COMPLEX, DIMENSION(:,:) :: A INTEGER :: N, LDA, LWORK, LRWORK, LIWORK, INFO INTEGER, DIMENSION(:) :: IWORK REAL, DIMENSION(:) :: W, RWORK SUBROUTINE HEEVD_64( JOBZ, UPLO, [N], A, [LDA], W, [WORK], [LWORK], * [RWORK], [LRWORK], [IWORK], [LIWORK], [INFO]) CHARACTER(LEN=1) :: JOBZ, UPLO COMPLEX, DIMENSION(:) :: WORK COMPLEX, DIMENSION(:,:) :: A INTEGER(8) :: N, LDA, LWORK, LRWORK, LIWORK, INFO INTEGER(8), DIMENSION(:) :: IWORK REAL, DIMENSION(:) :: W, RWORK
void cheevd(char jobz, char uplo, int n, complex *a, int lda, float *w, int *info);
void cheevd_64(char jobz, char uplo, long n, complex *a, long lda, float *w, long *info);
The divide and conquer algorithm makes very mild assumptions about floating point arithmetic. It will work on machines with a guard digit in add/subtract, or on those binary machines without guard digits which subtract like the Cray X-MP, Cray Y-MP, Cray C-90, or Cray-2. It could conceivably fail on hexadecimal or decimal machines without guard digits, but we know of none.
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.
If LRWORK = -1, then a workspace query is assumed; the routine only calculates the optimal size of the RWORK array, returns this value as the first entry of the RWORK array, and no error message related to LRWORK is issued by XERBLA.
If LIWORK = -1, then a workspace query is assumed; the routine only calculates the optimal size of the IWORK array, returns this value as the first entry of the IWORK array, and no error message related to LIWORK is issued by XERBLA.