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LAPACK
3.7.0
LAPACK: Linear Algebra PACKage
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subroutine zgtsv | ( | integer | N, |
integer | NRHS, | ||
complex*16, dimension( * ) | DL, | ||
complex*16, dimension( * ) | D, | ||
complex*16, dimension( * ) | DU, | ||
complex*16, dimension( ldb, * ) | B, | ||
integer | LDB, | ||
integer | INFO | ||
) |
ZGTSV computes the solution to system of linear equations A * X = B for GT matrices
Download ZGTSV + dependencies [TGZ] [ZIP] [TXT]
ZGTSV solves the equation A*X = B, where A is an N-by-N tridiagonal matrix, by Gaussian elimination with partial pivoting. Note that the equation A**T *X = B may be solved by interchanging the order of the arguments DU and DL.
[in] | N | N is INTEGER The order of the matrix A. N >= 0. |
[in] | NRHS | NRHS is INTEGER The number of right hand sides, i.e., the number of columns of the matrix B. NRHS >= 0. |
[in,out] | DL | DL is COMPLEX*16 array, dimension (N-1) On entry, DL must contain the (n-1) subdiagonal elements of A. On exit, DL is overwritten by the (n-2) elements of the second superdiagonal of the upper triangular matrix U from the LU factorization of A, in DL(1), ..., DL(n-2). |
[in,out] | D | D is COMPLEX*16 array, dimension (N) On entry, D must contain the diagonal elements of A. On exit, D is overwritten by the n diagonal elements of U. |
[in,out] | DU | DU is COMPLEX*16 array, dimension (N-1) On entry, DU must contain the (n-1) superdiagonal elements of A. On exit, DU is overwritten by the (n-1) elements of the first superdiagonal of U. |
[in,out] | B | B is COMPLEX*16 array, dimension (LDB,NRHS) On entry, the N-by-NRHS right hand side matrix B. On exit, if INFO = 0, the N-by-NRHS solution matrix X. |
[in] | LDB | LDB is INTEGER The leading dimension of the array B. LDB >= max(1,N). |
[out] | INFO | INFO is INTEGER = 0: successful exit < 0: if INFO = -i, the i-th argument had an illegal value > 0: if INFO = i, U(i,i) is exactly zero, and the solution has not been computed. The factorization has not been completed unless i = N. |
Definition at line 126 of file zgtsv.f.