zlanhs.f - Man Page
SRC/zlanhs.f
Synopsis
Functions/Subroutines
double precision function zlanhs (norm, n, a, lda, work)
ZLANHS returns the value of the 1-norm, Frobenius norm, infinity-norm, or the largest absolute value of any element of an upper Hessenberg matrix.
Function/Subroutine Documentation
double precision function zlanhs (character norm, integer n, complex*16, dimension( lda, * ) a, integer lda, double precision, dimension( * ) work)
ZLANHS returns the value of the 1-norm, Frobenius norm, infinity-norm, or the largest absolute value of any element of an upper Hessenberg matrix.
Purpose:
ZLANHS returns the value of the one norm, or the Frobenius norm, or the infinity norm, or the element of largest absolute value of a Hessenberg matrix A.
- Returns
ZLANHS
ZLANHS = ( 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 ZLANHS as described above.
N
N is INTEGER The order of the matrix A. N >= 0. When N = 0, ZLANHS is set to zero.
A
A is COMPLEX*16 array, dimension (LDA,N) The n by n upper Hessenberg matrix A; the part of A below the first sub-diagonal is not referenced.
LDA
LDA is INTEGER The leading dimension of the array A. LDA >= max(N,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.
Definition at line 108 of file zlanhs.f.
Author
Generated automatically by Doxygen for LAPACK from the source code.
Referenced By
The man page zlanhs(3) is an alias of zlanhs.f(3).
Tue Nov 28 2023 12:08:42 Version 3.12.0 LAPACK