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stpsv.f(3)                          LAPACK                          stpsv.f(3)

NAME
       stpsv.f -

SYNOPSIS
   Functions/Subroutines
       subroutine stpsv (UPLO, TRANS, DIAG, N, AP, X, INCX)
           STPSV

Function/Subroutine Documentation
   subroutine stpsv (characterUPLO, characterTRANS, characterDIAG, integerN,
       real, dimension(*)AP, real, dimension(*)X, integerINCX)
       STPSV Purpose:

            STPSV  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, supplied in packed form.

            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.

           AP

                     AP is REAL array of DIMENSION at least
                      ( ( n*( n + 1 ) )/2 ).
                      Before entry with  UPLO = 'U' or 'u', the array AP must
                      contain the upper triangular matrix packed sequentially,
                      column by column, so that AP( 1 ) contains a( 1, 1 ),
                      AP( 2 ) and AP( 3 ) contain a( 1, 2 ) and a( 2, 2 )
                      respectively, and so on.
                      Before entry with UPLO = 'L' or 'l', the array AP must
                      contain the lower triangular matrix packed sequentially,
                      column by column, so that AP( 1 ) contains a( 1, 1 ),
                      AP( 2 ) and AP( 3 ) contain a( 2, 1 ) and a( 3, 1 )
                      respectively, and so on.
                      Note that when  DIAG = 'U' or 'u', the diagonal elements of
                      A are not referenced, but are assumed to be unity.

           X

                     X is REAL 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.

       Author:
           Univ. of Tennessee

           Univ. of California Berkeley

           Univ. of Colorado Denver

           NAG Ltd.

       Date:
           November 2011

       Further Details:

             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.

       Definition at line 145 of file stpsv.f.

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

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