1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
|
.TH CLANGT l "15 June 2000" "LAPACK version 3.0" ")"
.SH NAME
CLANGT - return the value of the one norm, or the Frobenius norm, or the infinity norm, or the element of largest absolute value of a complex tridiagonal matrix A
.SH SYNOPSIS
.TP 14
REAL FUNCTION
CLANGT( NORM, N, DL, D, DU )
.TP 14
.ti +4
CHARACTER
NORM
.TP 14
.ti +4
INTEGER
N
.TP 14
.ti +4
COMPLEX
D( * ), DL( * ), DU( * )
.SH PURPOSE
CLANGT returns the value of the one norm, or the Frobenius norm, or the infinity norm, or the element of largest absolute value of a complex tridiagonal matrix A.
.SH DESCRIPTION
CLANGT returns the value
.br
CLANGT = ( max(abs(A(i,j))), NORM = 'M' or 'm'
.br
(
.br
( norm1(A), NORM = '1', 'O' or 'o'
.br
(
.br
( normI(A), NORM = 'I' or 'i'
.br
(
.br
( 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.
.SH ARGUMENTS
.TP 8
NORM (input) CHARACTER*1
Specifies the value to be returned in CLANGT as described
above.
.TP 8
N (input) INTEGER
The order of the matrix A. N >= 0. When N = 0, CLANGT is
set to zero.
.TP 8
DL (input) COMPLEX array, dimension (N-1)
The (n-1) sub-diagonal elements of A.
.TP 8
D (input) COMPLEX array, dimension (N)
The diagonal elements of A.
.TP 8
DU (input) COMPLEX array, dimension (N-1)
The (n-1) super-diagonal elements of A.
|
