DragonFly On-Line Manual Pages

Search: Section:  

clanhs.f(3)                         LAPACK                         clanhs.f(3)


NAME

       clanhs.f -


SYNOPSIS

   Functions/Subroutines
       REAL function clanhs (NORM, N, A, LDA, WORK)
           CLANHS returns the value of the 1-norm, Frobenius norm,
           infinity-norm, or the largest absolute value of any element of an
           upper Hessenberg matrix.

Function/Subroutine Documentation
   REAL function clanhs (characterNORM, integerN, complex, dimension( lda, *
       )A, integerLDA, real, dimension( * )WORK)
       CLANHS returns the value of the 1-norm, Frobenius norm, infinity-norm,
       or the largest absolute value of any element of an upper Hessenberg
       matrix.

       Purpose:

            CLANHS  returns the value of the one norm,  or the Frobenius norm, or
            the  infinity norm,  or the  element of  largest absolute value  of a
            Hessenberg matrix A.

       Returns:
           CLANHS

               CLANHS = ( max(abs(A(i,j))), NORM = 'M' or 'm'
                        (
                        ( norm1(A),         NORM = '1', 'O' or 'o'
                        (
                        ( normI(A),         NORM = 'I' or 'i'
                        (
                        ( normF(A),         NORM = 'F', 'f', 'E' or 'e'

            where  norm1  denotes the  one norm of a matrix (maximum column sum),
            normI  denotes the  infinity norm  of a matrix  (maximum row sum) and
            normF  denotes the  Frobenius norm of a matrix (square root of sum of
            squares).  Note that  max(abs(A(i,j)))  is not a consistent matrix norm.

       Parameters:
           NORM

                     NORM is CHARACTER*1
                     Specifies the value to be returned in CLANHS as described
                     above.

           N

                     N is INTEGER
                     The order of the matrix A.  N >= 0.  When N = 0, CLANHS is
                     set to zero.

           A

                     A is COMPLEX array, dimension (LDA,N)
                     The n by n upper Hessenberg matrix A; the part of A below the
                     first sub-diagonal is not referenced.

           LDA

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

           WORK

                     WORK is REAL array, dimension (MAX(1,LWORK)),
                     where LWORK >= N when NORM = 'I'; otherwise, WORK is not
                     referenced.

       Author:
           Univ. of Tennessee

           Univ. of California Berkeley

           Univ. of Colorado Denver

           NAG Ltd.

       Date:
           September 2012

       Definition at line 110 of file clanhs.f.

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

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

Search: Section: