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ZLANGB(l)					)					ZLANGB(l)

NAME
       ZLANGB - return 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 band matrix A,  with	kl  sub-diagonals
       and ku super-diagonals

SYNOPSIS
       DOUBLE PRECISION FUNCTION ZLANGB( NORM, N, KL, KU, AB, LDAB, WORK )

	   CHARACTER	NORM

	   INTEGER	KL, KU, LDAB, N

	   DOUBLE	PRECISION WORK( * )

	   COMPLEX*16	AB( LDAB, * )

PURPOSE
       ZLANGB  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 band matrix A,  with	kl  sub-diagonals
       and ku super-diagonals.

DESCRIPTION
       ZLANGB returns the value

	  ZLANGB = ( 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  matrix
       norm.

ARGUMENTS
       NORM    (input) CHARACTER*1
	       Specifies the value to be returned in ZLANGB as described above.

       N       (input) INTEGER
	       The order of the matrix A.  N >= 0.  When N = 0, ZLANGB is set to zero.

       KL      (input) INTEGER
	       The number of sub-diagonals of the matrix A.  KL >= 0.

       KU      (input) INTEGER
	       The number of super-diagonals of the matrix A.  KU >= 0.

       AB      (input) COMPLEX*16 array, dimension (LDAB,N)
	       The band matrix A, stored in rows 1 to KL+KU+1.	The j-th column of A is stored in
	       the  j-th  column of the array AB as follows: AB(ku+1+i-j,j) = A(i,j) for max(1,j-
	       ku)<=i<=min(n,j+kl).

       LDAB    (input) INTEGER
	       The leading dimension of the array AB.  LDAB >= KL+KU+1.

       WORK    (workspace) DOUBLE PRECISION array, dimension (LWORK),
	       where LWORK >= N when NORM = 'I'; otherwise, WORK is not referenced.

LAPACK version 3.0			   15 June 2000 				ZLANGB(l)
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