dgtsl
dgtsl - (obsolete) solve the linear system Ax = b for a tridiagonal matrix A and vectors b
and x.
SUBROUTINE DGTSL( N, SUB, DIAG, SUPER, B, INFO)
INTEGER N, INFO
DOUBLE PRECISION SUB(*), DIAG(*), SUPER(*), B(*)
SUBROUTINE DGTSL_64( N, SUB, DIAG, SUPER, B, INFO)
INTEGER*8 N, INFO
DOUBLE PRECISION SUB(*), DIAG(*), SUPER(*), B(*)
#include <sunperf.h>
void dgtsl(int n, double *sub, double *diag, double *super, double *b, int *info);
void dgtsl_64(long n, double *sub, double *diag, double *super, double *b, long *info);
-
* N (input)
-
Order of the matrix A. N >= 0.
-
* SUB (input)
-
Subdiagonal of A. SUB(2) through SUB(N) contain the
subdiagonal and SUB(1) is not referenced.
-
* DIAG (input)
-
Diagonal of A.
-
* SUPER (input)
-
Superdiagonal of A. SUPER(1) through SUPER(N-1) contain
the superdiagonal and SUPER(N) is not referenced.
-
* B (input/output)
-
On entry, the right-hand side vector b.
On exit, the solution vector x.
-
* INFO (output)
-
On exit:
INFO = 0 Subroutine completed normally.
INFO < 0 Returns a value k when the kth element of the diagonal
becomes exactly zero.