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dtrsv.f(3)                          LAPACK                          dtrsv.f(3)

NAME
       dtrsv.f -

SYNOPSIS
   Functions/Subroutines
       subroutine dtrsv (UPLO, TRANS, DIAG, N, A, LDA, X, INCX)
           DTRSV

Function/Subroutine Documentation
   subroutine dtrsv (characterUPLO, characterTRANS, characterDIAG, integerN,
       double precision, dimension(lda,*)A, integerLDA, double precision,
       dimension(*)X, integerINCX)
       DTRSV Purpose:

            DTRSV  solves one of the systems of equations

               A*x = b,   or   A**T*x = b,

            where b and x are n element vectors and A is an n by n unit, or
            non-unit, upper or lower triangular matrix.

            No test for singularity or near-singularity is included in this
            routine. Such tests must be performed before calling this routine.

       Parameters:
           UPLO

                     UPLO is CHARACTER*1
                      On entry, UPLO specifies whether the matrix is an upper or
                      lower triangular matrix as follows:

                         UPLO = 'U' or 'u'   A is an upper triangular matrix.

                         UPLO = 'L' or 'l'   A is a lower triangular matrix.

           TRANS

                     TRANS is CHARACTER*1
                      On entry, TRANS specifies the equations to be solved as
                      follows:

                         TRANS = 'N' or 'n'   A*x = b.

                         TRANS = 'T' or 't'   A**T*x = b.

                         TRANS = 'C' or 'c'   A**T*x = b.

           DIAG

                     DIAG is CHARACTER*1
                      On entry, DIAG specifies whether or not A is unit
                      triangular as follows:

                         DIAG = 'U' or 'u'   A is assumed to be unit triangular.

                         DIAG = 'N' or 'n'   A is not assumed to be unit
                                             triangular.

           N

                     N is INTEGER
                      On entry, N specifies the order of the matrix A.
                      N must be at least zero.

           A

                     A is DOUBLE PRECISION array of DIMENSION ( LDA, n ).
                      Before entry with  UPLO = 'U' or 'u', the leading n by n
                      upper triangular part of the array A must contain the upper
                      triangular matrix and the strictly lower triangular part of
                      A is not referenced.
                      Before entry with UPLO = 'L' or 'l', the leading n by n
                      lower triangular part of the array A must contain the lower
                      triangular matrix and the strictly upper triangular part of
                      A is not referenced.
                      Note that when  DIAG = 'U' or 'u', the diagonal elements of
                      A are not referenced either, but are assumed to be unity.

           LDA

                     LDA is INTEGER
                      On entry, LDA specifies the first dimension of A as declared
                      in the calling (sub) program. LDA must be at least
                      max( 1, n ).

           X

                     X is DOUBLE PRECISION array of dimension at least
                      ( 1 + ( n - 1 )*abs( INCX ) ).
                      Before entry, the incremented array X must contain the n
                      element right-hand side vector b. On exit, X is overwritten
                      with the solution vector x.

           INCX

                     INCX is INTEGER
                      On entry, INCX specifies the increment for the elements of
                      X. INCX must not be zero.

             Level 2 Blas routine.

             -- Written on 22-October-1986.
                Jack Dongarra, Argonne National Lab.
                Jeremy Du Croz, Nag Central Office.
                Sven Hammarling, Nag Central Office.
                Richard Hanson, Sandia National Labs.

       Author:
           Univ. of Tennessee

           Univ. of California Berkeley

           Univ. of Colorado Denver

           NAG Ltd.

       Date:
           November 2011

       Definition at line 144 of file dtrsv.f.

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

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