SRC/zlansb.f(3)            Library Functions Manual            SRC/zlansb.f(3)

NAME
       SRC/zlansb.f

SYNOPSIS
   Functions/Subroutines
       double precision function zlansb (norm, uplo, n, k, ab, ldab, work)
           ZLANSB returns the value of the 1-norm, or the Frobenius norm, or
           the infinity norm, or the element of largest absolute value of a
           symmetric band matrix.

Function/Subroutine Documentation
   double precision function zlansb (character norm, character uplo, integer
       n, integer k, complex*16, dimension( ldab, * ) ab, integer ldab, double
       precision, dimension( * ) work)
       ZLANSB returns the value of the 1-norm, or the Frobenius norm, or the
       infinity norm, or the element of largest absolute value of a symmetric
       band matrix.

       Purpose:


           !>
           !> ZLANSB  returns the value of the one norm,  or the Frobenius norm, or
           !> the  infinity norm,  or the element of  largest absolute value  of an
           !> n by n symmetric band matrix A,  with k super-diagonals.
           !>

       Returns
           ZLANSB

           !>
           !>    ZLANSB = ( 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 ZLANSB as described
           !>          above.
           !>

           UPLO

           !>          UPLO is CHARACTER*1
           !>          Specifies whether the upper or lower triangular part of the
           !>          band matrix A is supplied.
           !>          = 'U':  Upper triangular part is supplied
           !>          = 'L':  Lower triangular part is supplied
           !>

           N

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

           K

           !>          K is INTEGER
           !>          The number of super-diagonals or sub-diagonals of the
           !>          band matrix A.  K >= 0.
           !>

           AB

           !>          AB is COMPLEX*16 array, dimension (LDAB,N)
           !>          The upper or lower triangle of the symmetric band matrix A,
           !>          stored in the first K+1 rows of AB.  The j-th column of A is
           !>          stored in the j-th column of the array AB as follows:
           !>          if UPLO = 'U', AB(k+1+i-j,j) = A(i,j) for max(1,j-k)<=i<=j;
           !>          if UPLO = 'L', AB(1+i-j,j)   = A(i,j) for j<=i<=min(n,j+k).
           !>

           LDAB

           !>          LDAB is INTEGER
           !>          The leading dimension of the array AB.  LDAB >= K+1.
           !>

           WORK

           !>          WORK is DOUBLE PRECISION array, dimension (MAX(1,LWORK)),
           !>          where LWORK >= N when NORM = 'I' or '1' or 'O'; otherwise,
           !>          WORK is not referenced.
           !>

       Author
           Univ. of Tennessee


           Univ. of California Berkeley


           Univ. of Colorado Denver


           NAG Ltd.

       Definition at line 128 of file zlansb.f.

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

LAPACK                          Version 3.12.0                 SRC/zlansb.f(3)