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dlangb(3) [debian man page]

dlangb.f(3)							      LAPACK							       dlangb.f(3)

NAME

       dlangb.f -

SYNOPSIS

   Functions/Subroutines
       DOUBLE PRECISION function dlangb (NORM, N, KL, KU, AB, LDAB, WORK)
	   DLANGB

Function/Subroutine Documentation
   DOUBLE PRECISION function dlangb (characterNORM, integerN, integerKL, integerKU, double precision, dimension( ldab, * )AB, integerLDAB, double
       precision, dimension( * )WORK)
       DLANGB

       Purpose:

	    DLANGB  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.

       Returns:
	   DLANGB

	       DLANGB = ( 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 DLANGB as described
		     above.

	   N

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

	   KL

		     KL is INTEGER
		     The number of sub-diagonals of the matrix A.  KL >= 0.

	   KU

		     KU is INTEGER
		     The number of super-diagonals of the matrix A.  KU >= 0.

	   AB

		     AB is DOUBLE PRECISION 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

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

	   WORK

		     WORK is DOUBLE PRECISION 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:
	   November 2011

       Definition at line 124 of file dlangb.f.

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

Version 3.4.1							  Sun May 26 2013						       dlangb.f(3)

Check Out this Related Man Page

DLANGB(l)								 )								 DLANGB(l)

NAME

       DLANGB - 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 DLANGB( NORM, N, KL, KU, AB, LDAB, WORK )

	   CHARACTER	NORM

	   INTEGER	KL, KU, LDAB, N

	   DOUBLE	PRECISION AB( LDAB, * ), WORK( * )

PURPOSE

       DLANGB 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

       DLANGB returns the value

	  DLANGB = ( 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 DLANGB as described above.

       N       (input) INTEGER
	       The order of the matrix A.  N >= 0.  When N = 0, DLANGB 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) DOUBLE PRECISION 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 							 DLANGB(l)
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