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cgtsv.f(3)                          LAPACK                          cgtsv.f(3)

NAME
       cgtsv.f -

SYNOPSIS
   Functions/Subroutines
       subroutine cgtsv (N, NRHS, DL, D, DU, B, LDB, INFO)
            CGTSV computes the solution to system of linear equations A * X =
           B for GT matrices

Function/Subroutine Documentation
   subroutine cgtsv (integerN, integerNRHS, complex, dimension( * )DL,
       complex, dimension( * )D, complex, dimension( * )DU, complex,
       dimension( ldb, * )B, integerLDB, integerINFO)
        CGTSV computes the solution to system of linear equations A * X = B
       for GT matrices

       Purpose:

            CGTSV  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.

       Parameters:
           N

                     N is INTEGER
                     The order of the matrix A.  N >= 0.

           NRHS

                     NRHS is INTEGER
                     The number of right hand sides, i.e., the number of columns
                     of the matrix B.  NRHS >= 0.

           DL

                     DL is COMPLEX 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).

           D

                     D is COMPLEX 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.

           DU

                     DU is COMPLEX 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.

           B

                     B is COMPLEX 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.

           LDB

                     LDB is INTEGER
                     The leading dimension of the array B.  LDB >= max(1,N).

           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.

       Author:
           Univ. of Tennessee

           Univ. of California Berkeley

           Univ. of Colorado Denver

           NAG Ltd.

       Date:
           September 2012

       Definition at line 125 of file cgtsv.f.

Author
       Generated automatically by Doxygen for LAPACK from the source code.

Version 3.4.2                   Sat Nov 16 2013                     cgtsv.f(3)