dpttrs - solve a tridiagonal system of the form A * X = B using the L*D*L' factorization of A computed by DPTTRF
SUBROUTINE DPTTRS(N, NRHS, D, E, B, LDB, INFO) INTEGER N, NRHS, LDB, INFO DOUBLE PRECISION D(*), E(*), B(LDB,*) SUBROUTINE DPTTRS_64(N, NRHS, D, E, B, LDB, INFO) INTEGER*8 N, NRHS, LDB, INFO DOUBLE PRECISION D(*), E(*), B(LDB,*) F95 INTERFACE SUBROUTINE PTTRS(N, NRHS, D, E, B, LDB, INFO) INTEGER :: N, NRHS, LDB, INFO REAL(8), DIMENSION(:) :: D, E REAL(8), DIMENSION(:,:) :: B SUBROUTINE PTTRS_64(N, NRHS, D, E, B, LDB, INFO) INTEGER(8) :: N, NRHS, LDB, INFO REAL(8), DIMENSION(:) :: D, E REAL(8), DIMENSION(:,:) :: B C INTERFACE #include <sunperf.h> void dpttrs(int n, int nrhs, double *d, double *e, double *b, int ldb, int *info); void dpttrs_64(long n, long nrhs, double *d, double *e, double *b, long ldb, long *info);
Oracle Solaris Studio Performance Library dpttrs(3P) NAME dpttrs - solve a tridiagonal system of the form A * X = B using the L*D*L' factorization of A computed by DPTTRF SYNOPSIS SUBROUTINE DPTTRS(N, NRHS, D, E, B, LDB, INFO) INTEGER N, NRHS, LDB, INFO DOUBLE PRECISION D(*), E(*), B(LDB,*) SUBROUTINE DPTTRS_64(N, NRHS, D, E, B, LDB, INFO) INTEGER*8 N, NRHS, LDB, INFO DOUBLE PRECISION D(*), E(*), B(LDB,*) F95 INTERFACE SUBROUTINE PTTRS(N, NRHS, D, E, B, LDB, INFO) INTEGER :: N, NRHS, LDB, INFO REAL(8), DIMENSION(:) :: D, E REAL(8), DIMENSION(:,:) :: B SUBROUTINE PTTRS_64(N, NRHS, D, E, B, LDB, INFO) INTEGER(8) :: N, NRHS, LDB, INFO REAL(8), DIMENSION(:) :: D, E REAL(8), DIMENSION(:,:) :: B C INTERFACE #include <sunperf.h> void dpttrs(int n, int nrhs, double *d, double *e, double *b, int ldb, int *info); void dpttrs_64(long n, long nrhs, double *d, double *e, double *b, long ldb, long *info); PURPOSE dpttrs solves a tridiagonal system of the form A * X = B using the L*D*L' factorization of A computed by DPTTRF. D is a diagonal matrix specified in the vector D, L is a unit bidiagonal matrix whose subdiagonal is specified in the vector E, and X and B are N by NRHS matrices. ARGUMENTS N (input) The order of the tridiagonal matrix A. N >= 0. NRHS (input) The number of right hand sides, i.e., the number of columns of the matrix B. NRHS >= 0. D (input) The n diagonal elements of the diagonal matrix D from the L*D*L' factorization of A. E (input) The (n-1) subdiagonal elements of the unit bidiagonal factor L from the L*D*L' factorization of A. E can also be regarded as the superdiagonal of the unit bidiagonal factor U from the factorization A = U'*D*U. B (input/output) On entry, the right hand side vectors B for the system of linear equations. On exit, the solution vectors, X. LDB (input) The leading dimension of the array B. LDB >= max(1,N). INFO (output) = 0: successful exit < 0: if INFO = -k, the k-th argument had an illegal value 7 Nov 2015 dpttrs(3P)