slantp(l) [redhat man page]

SLANTP(l)								 )								 SLANTP(l)

NAME

       SLANTP  - return the value of the one norm, or the Frobenius norm, or the infinity norm, or the element of largest absolute value of a tri-
       angular matrix A, supplied in packed form

SYNOPSIS

       REAL FUNCTION SLANTP( NORM, UPLO, DIAG, N, AP, WORK )

	   CHARACTER DIAG, NORM, UPLO

	   INTEGER   N

	   REAL      AP( * ), WORK( * )

PURPOSE

       SLANTP returns the value of the one norm, or the Frobenius norm, or the infinity norm, or the element of largest absolute value of a trian-
       gular matrix A, supplied in packed form.

DESCRIPTION

       SLANTP returns the value

	  SLANTP = ( 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 SLANTP as described above.

       UPLO    (input) CHARACTER*1
	       Specifies whether the matrix A is upper or lower triangular.  = 'U':  Upper triangular
	       = 'L':  Lower triangular

       DIAG    (input) CHARACTER*1
	       Specifies whether or not the matrix A is unit triangular.  = 'N':  Non-unit triangular
	       = 'U':  Unit triangular

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

       AP      (input) REAL array, dimension (N*(N+1)/2)
	       The upper or lower triangular matrix A, packed columnwise in a linear array.  The j-th column of A is stored in	the  array  AP	as
	       follows:  if  UPLO = 'U', AP(i + (j-1)*j/2) = A(i,j) for 1<=i<=j; if UPLO = 'L', AP(i + (j-1)*(2n-j)/2) = A(i,j) for j<=i<=n.  Note
	       that when DIAG = 'U', the elements of the array AP corresponding to the diagonal elements of the matrix A are not  referenced,  but
	       are assumed to be one.

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

LAPACK version 3.0						   15 June 2000 							 SLANTP(l)

slantp.f(3)							      LAPACK							       slantp.f(3)

NAME

       slantp.f -

SYNOPSIS

   Functions/Subroutines
       REAL function slantp (NORM, UPLO, DIAG, N, AP, WORK)
	   SLANTP returns the value of the 1-norm, or the Frobenius norm, or the infinity norm, or the element of largest absolute value of a
	   triangular matrix supplied in packed form.

Function/Subroutine Documentation
   REAL function slantp (characterNORM, characterUPLO, characterDIAG, integerN, real, dimension( * )AP, real, dimension( * )WORK)
       SLANTP returns the value of the 1-norm, or the Frobenius norm, or the infinity norm, or the element of largest absolute value of a
       triangular matrix supplied in packed form.

       Purpose:

	    SLANTP  returns the value of the one norm,	or the Frobenius norm, or
	    the  infinity norm,  or the  element of  largest absolute value  of a
	    triangular matrix A, supplied in packed form.

       Returns:
	   SLANTP

	       SLANTP = ( 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 SLANTP as described
		     above.

	   UPLO

		     UPLO is CHARACTER*1
		     Specifies whether the matrix A is upper or lower triangular.
		     = 'U':  Upper triangular
		     = 'L':  Lower triangular

	   DIAG

		     DIAG is CHARACTER*1
		     Specifies whether or not the matrix A is unit triangular.
		     = 'N':  Non-unit triangular
		     = 'U':  Unit triangular

	   N

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

	   AP

		     AP is REAL array, dimension (N*(N+1)/2)
		     The upper or lower triangular matrix A, packed columnwise in
		     a linear array.  The j-th column of A is stored in the array
		     AP as follows:
		     if UPLO = 'U', AP(i + (j-1)*j/2) = A(i,j) for 1<=i<=j;
		     if UPLO = 'L', AP(i + (j-1)*(2n-j)/2) = A(i,j) for j<=i<=n.
		     Note that when DIAG = 'U', the elements of the array AP
		     corresponding to the diagonal elements of the matrix A are
		     not referenced, but are assumed to be one.

	   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 125 of file slantp.f.

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

Version 3.4.2							  Tue Sep 25 2012						       slantp.f(3)