
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 1norm, 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 1norm, 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': Nonunit 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 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.
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) 
