ssterf - compute all eigenvalues of a symmetric tridiagonal matrix using the Pal-Walker-Kahan variant of the QL or QR algorithm
SUBROUTINE SSTERF(N, D, E, INFO) INTEGER N, INFO REAL D(*), E(*) SUBROUTINE SSTERF_64(N, D, E, INFO) INTEGER*8 N, INFO REAL D(*), E(*) F95 INTERFACE SUBROUTINE STERF(N, D, E, INFO) INTEGER :: N, INFO REAL, DIMENSION(:) :: D, E SUBROUTINE STERF_64(N, D, E, INFO) INTEGER(8) :: N, INFO REAL, DIMENSION(:) :: D, E C INTERFACE #include <sunperf.h> void ssterf(int n, float *d, float *e, int *info); void ssterf_64(long n, float *d, float *e, long *info);
Oracle Solaris Studio Performance Library ssterf(3P) NAME ssterf - compute all eigenvalues of a symmetric tridiagonal matrix using the Pal-Walker-Kahan variant of the QL or QR algorithm SYNOPSIS SUBROUTINE SSTERF(N, D, E, INFO) INTEGER N, INFO REAL D(*), E(*) SUBROUTINE SSTERF_64(N, D, E, INFO) INTEGER*8 N, INFO REAL D(*), E(*) F95 INTERFACE SUBROUTINE STERF(N, D, E, INFO) INTEGER :: N, INFO REAL, DIMENSION(:) :: D, E SUBROUTINE STERF_64(N, D, E, INFO) INTEGER(8) :: N, INFO REAL, DIMENSION(:) :: D, E C INTERFACE #include <sunperf.h> void ssterf(int n, float *d, float *e, int *info); void ssterf_64(long n, float *d, float *e, long *info); PURPOSE ssterf computes all eigenvalues of a symmetric tridiagonal matrix using the Pal-Walker-Kahan variant of the QL or QR algorithm. ARGUMENTS N (input) The order of the matrix. N >= 0. D (input/output) On entry, the n diagonal elements of the tridiagonal matrix. On exit, if INFO = 0, the eigenvalues in ascending order. E (input/output) On entry, the (n-1) subdiagonal elements of the tridiagonal matrix. On exit, E has been destroyed. INFO (output) = 0: successful exit < 0: if INFO = -i, the i-th argument had an illegal value > 0: the algorithm failed to find all of the eigenvalues in a total of 30*N iterations; if INFO = i, then i elements of E have not converged to zero. 7 Nov 2015 ssterf(3P)