DPTTRSV - solve one of the triangular systems L**T* X = B, or L *
X = B,
- SUBROUTINE
DPTTRSV(
- TRANS, N, NRHS, D, E, B, LDB, INFO )
CHARACTER TRANS INTEGER INFO, LDB, N, NRHS DOUBLE PRECISION D( * )
DOUBLE PRECISION B( LDB, * ), E( * )
DPTTRSV solves one of the triangular systems
L**T* X = B, or L * X = B, where L is the Cholesky factor of a Hermitian
positive
definite tridiagonal matrix A such that
A = L*D*L**H (computed by DPTTRF).
- TRANS (input)
CHARACTER
- Specifies the form of the system of equations:
= 'N': L * X = B (No transpose)
= 'T': L**T * X = B (Transpose)
- N (input) INTEGER
- The order of the tridiagonal matrix A. N >= 0.
- NRHS (input) INTEGER
- The number of right hand sides, i.e., the number of columns of the matrix
B. NRHS >= 0.
- D (input) REAL array, dimension
(N)
- The n diagonal elements of the diagonal matrix D from the factorization
computed by DPTTRF.
- E (input) COMPLEX array, dimension
(N-1)
- The (n-1) off-diagonal elements of the unit bidiagonal factor U or L from
the factorization computed by DPTTRF (see UPLO).
- B (input/output) COMPLEX array,
dimension (LDB,NRHS)
- On entry, the right hand side matrix B. On exit, the solution matrix
X.
- LDB (input) INTEGER
- The leading dimension of the array B. LDB >= max(1,N).
- INFO (output) INTEGER
- = 0: successful exit
< 0: if INFO = -i, the i-th argument had an illegal value