SUBROUTINE SSYGV( ITYPE, JOBZ, UPLO, N, A, LDA, B, LDB, W, WORK, * LDWORK, INFO) CHARACTER * 1 JOBZ, UPLO INTEGER ITYPE, N, LDA, LDB, LDWORK, INFO REAL A(LDA,*), B(LDB,*), W(*), WORK(*) SUBROUTINE SSYGV_64( ITYPE, JOBZ, UPLO, N, A, LDA, B, LDB, W, WORK, * LDWORK, INFO) CHARACTER * 1 JOBZ, UPLO INTEGER*8 ITYPE, N, LDA, LDB, LDWORK, INFO REAL A(LDA,*), B(LDB,*), W(*), WORK(*)
SUBROUTINE SYGV( ITYPE, JOBZ, UPLO, N, A, [LDA], B, [LDB], W, [WORK], * [LDWORK], [INFO]) CHARACTER(LEN=1) :: JOBZ, UPLO INTEGER :: ITYPE, N, LDA, LDB, LDWORK, INFO REAL, DIMENSION(:) :: W, WORK REAL, DIMENSION(:,:) :: A, B SUBROUTINE SYGV_64( ITYPE, JOBZ, UPLO, N, A, [LDA], B, [LDB], W, * [WORK], [LDWORK], [INFO]) CHARACTER(LEN=1) :: JOBZ, UPLO INTEGER(8) :: ITYPE, N, LDA, LDB, LDWORK, INFO REAL, DIMENSION(:) :: W, WORK REAL, DIMENSION(:,:) :: A, B
void ssygv(int itype, char jobz, char uplo, int n, float *a, int lda, float *b, int ldb, float *w, int *info);
void ssygv_64(long itype, char jobz, char uplo, long n, float *a, long lda, float *b, long ldb, float *w, long *info);
positive definite.
On exit, if JOBZ = 'V', then if INFO = 0, A contains the matrix Z of eigenvectors. The eigenvectors are normalized as follows: if ITYPE = 1 or 2, Z**T*B*Z = I; if ITYPE = 3, Z**T*inv(B)*Z = I. If JOBZ = 'N', then on exit the upper triangle (if UPLO='U') or the lower triangle (if UPLO='L') of A, including the diagonal, is destroyed.
On exit, if INFO <= N, the part of B containing the matrix is overwritten by the triangular factor U or L from the Cholesky factorization B = U**T*U or B = L*L**T.
If LDWORK = -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 LDWORK is issued by XERBLA.