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
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
|
SUBROUTINE ZLASET( UPLO, M, N, ALPHA, BETA, A, LDA )
*
* -- LAPACK auxiliary routine (version 3.1) --
* Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd..
* November 2006
*
* .. Scalar Arguments ..
CHARACTER UPLO
INTEGER LDA, M, N
COMPLEX*16 ALPHA, BETA
* ..
* .. Array Arguments ..
COMPLEX*16 A( LDA, * )
* ..
*
* Purpose
* =======
*
* ZLASET initializes a 2-D array A to BETA on the diagonal and
* ALPHA on the offdiagonals.
*
* Arguments
* =========
*
* UPLO (input) CHARACTER*1
* Specifies the part of the matrix A to be set.
* = 'U': Upper triangular part is set. The lower triangle
* is unchanged.
* = 'L': Lower triangular part is set. The upper triangle
* is unchanged.
* Otherwise: All of the matrix A is set.
*
* M (input) INTEGER
* On entry, M specifies the number of rows of A.
*
* N (input) INTEGER
* On entry, N specifies the number of columns of A.
*
* ALPHA (input) COMPLEX*16
* All the offdiagonal array elements are set to ALPHA.
*
* BETA (input) COMPLEX*16
* All the diagonal array elements are set to BETA.
*
* A (input/output) COMPLEX*16 array, dimension (LDA,N)
* On entry, the m by n matrix A.
* On exit, A(i,j) = ALPHA, 1 <= i <= m, 1 <= j <= n, i.ne.j;
* A(i,i) = BETA , 1 <= i <= min(m,n)
*
* LDA (input) INTEGER
* The leading dimension of the array A. LDA >= max(1,M).
*
* =====================================================================
*
* .. Local Scalars ..
INTEGER I, J
* ..
* .. External Functions ..
LOGICAL LSAME
EXTERNAL LSAME
* ..
* .. Intrinsic Functions ..
INTRINSIC MIN
* ..
* .. Executable Statements ..
*
IF( LSAME( UPLO, 'U' ) ) THEN
*
* Set the diagonal to BETA and the strictly upper triangular
* part of the array to ALPHA.
*
DO 20 J = 2, N
DO 10 I = 1, MIN( J-1, M )
A( I, J ) = ALPHA
10 CONTINUE
20 CONTINUE
DO 30 I = 1, MIN( N, M )
A( I, I ) = BETA
30 CONTINUE
*
ELSE IF( LSAME( UPLO, 'L' ) ) THEN
*
* Set the diagonal to BETA and the strictly lower triangular
* part of the array to ALPHA.
*
DO 50 J = 1, MIN( M, N )
DO 40 I = J + 1, M
A( I, J ) = ALPHA
40 CONTINUE
50 CONTINUE
DO 60 I = 1, MIN( N, M )
A( I, I ) = BETA
60 CONTINUE
*
ELSE
*
* Set the array to BETA on the diagonal and ALPHA on the
* offdiagonal.
*
DO 80 J = 1, N
DO 70 I = 1, M
A( I, J ) = ALPHA
70 CONTINUE
80 CONTINUE
DO 90 I = 1, MIN( M, N )
A( I, I ) = BETA
90 CONTINUE
END IF
*
RETURN
*
* End of ZLASET
*
END
|