
dlansp.f(3) LAPACK dlansp.f(3)
NAME
dlansp.f 
SYNOPSIS
Functions/Subroutines
DOUBLE PRECISION function dlansp (NORM, UPLO, N, AP, WORK)
DLANSP returns the value of the 1norm, or the Frobenius norm, or the infinity norm,
or the element of largest absolute value of a symmetric matrix supplied in packed
form.
Function/Subroutine Documentation
DOUBLE PRECISION function dlansp (characterNORM, characterUPLO, integerN, double precision,
dimension( * )AP, double precision, dimension( * )WORK)
DLANSP returns the value of the 1norm, or the Frobenius norm, or the infinity norm, or
the element of largest absolute value of a symmetric matrix supplied in packed form.
Purpose:
DLANSP returns the value of the one norm, or the Frobenius norm, or
the infinity norm, or the element of largest absolute value of a
real symmetric matrix A, supplied in packed form.
Returns:
DLANSP
DLANSP = ( 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 DLANSP as described
above.
UPLO
UPLO is CHARACTER*1
Specifies whether the upper or lower triangular part of the
symmetric matrix A is supplied.
= 'U': Upper triangular part of A is supplied
= 'L': Lower triangular part of A is supplied
N
N is INTEGER
The order of the matrix A. N >= 0. When N = 0, DLANSP is
set to zero.
AP
AP is DOUBLE PRECISION array, dimension (N*(N+1)/2)
The upper or lower triangle of the symmetric matrix A, packed
columnwise in a linear array. The jth column of A is stored
in the array AP as follows:
if UPLO = 'U', AP(i + (j1)*j/2) = A(i,j) for 1<=i<=j;
if UPLO = 'L', AP(i + (j1)*(2nj)/2) = A(i,j) for j<=i<=n.
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.
Date:
September 2012
Definition at line 115 of file dlansp.f.
Author
Generated automatically by Doxygen for LAPACK from the source code.
Version 3.4.2 Tue Sep 25 2012 dlansp.f(3) 
