table of contents
/home/abuild/rpmbuild/BUILD/lapack-3.12.0/SRC/slantp.f(3) | Library Functions Manual | /home/abuild/rpmbuild/BUILD/lapack-3.12.0/SRC/slantp.f(3) |
NAME¶
/home/abuild/rpmbuild/BUILD/lapack-3.12.0/SRC/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 (character norm, character uplo, character diag, integer n, 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.
Definition at line 123 of file slantp.f.
Author¶
Generated automatically by Doxygen for LAPACK from the source code.
Version 3.12.0 | LAPACK |