annotate libcruft/lapack/slasda.f @ 7789:82be108cc558

First attempt at single precision tyeps * * * corrections to qrupdate single precision routines * * * prefer demotion to single over promotion to double * * * Add single precision support to log2 function * * * Trivial PROJECT file update * * * Cache optimized hermitian/transpose methods * * * Add tests for tranpose/hermitian and ChangeLog entry for new transpose code
author David Bateman <dbateman@free.fr>
date Sun, 27 Apr 2008 22:34:17 +0200
parents
children
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
rev   line source
7789
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
1 SUBROUTINE SLASDA( ICOMPQ, SMLSIZ, N, SQRE, D, E, U, LDU, VT, K,
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
2 $ DIFL, DIFR, Z, POLES, GIVPTR, GIVCOL, LDGCOL,
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
3 $ PERM, GIVNUM, C, S, WORK, IWORK, INFO )
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
4 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
5 * -- LAPACK auxiliary routine (version 3.1) --
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
6 * Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd..
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
7 * November 2006
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
8 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
9 * .. Scalar Arguments ..
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
10 INTEGER ICOMPQ, INFO, LDGCOL, LDU, N, SMLSIZ, SQRE
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
11 * ..
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
12 * .. Array Arguments ..
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
13 INTEGER GIVCOL( LDGCOL, * ), GIVPTR( * ), IWORK( * ),
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
14 $ K( * ), PERM( LDGCOL, * )
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
15 REAL C( * ), D( * ), DIFL( LDU, * ), DIFR( LDU, * ),
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
16 $ E( * ), GIVNUM( LDU, * ), POLES( LDU, * ),
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
17 $ S( * ), U( LDU, * ), VT( LDU, * ), WORK( * ),
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
18 $ Z( LDU, * )
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
19 * ..
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
20 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
21 * Purpose
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
22 * =======
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
23 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
24 * Using a divide and conquer approach, SLASDA computes the singular
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
25 * value decomposition (SVD) of a real upper bidiagonal N-by-M matrix
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
26 * B with diagonal D and offdiagonal E, where M = N + SQRE. The
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
27 * algorithm computes the singular values in the SVD B = U * S * VT.
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
28 * The orthogonal matrices U and VT are optionally computed in
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
29 * compact form.
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
30 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
31 * A related subroutine, SLASD0, computes the singular values and
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
32 * the singular vectors in explicit form.
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
33 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
34 * Arguments
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
35 * =========
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
36 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
37 * ICOMPQ (input) INTEGER
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
38 * Specifies whether singular vectors are to be computed
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
39 * in compact form, as follows
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
40 * = 0: Compute singular values only.
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
41 * = 1: Compute singular vectors of upper bidiagonal
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
42 * matrix in compact form.
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
43 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
44 * SMLSIZ (input) INTEGER
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
45 * The maximum size of the subproblems at the bottom of the
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
46 * computation tree.
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
47 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
48 * N (input) INTEGER
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
49 * The row dimension of the upper bidiagonal matrix. This is
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
50 * also the dimension of the main diagonal array D.
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
51 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
52 * SQRE (input) INTEGER
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
53 * Specifies the column dimension of the bidiagonal matrix.
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
54 * = 0: The bidiagonal matrix has column dimension M = N;
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
55 * = 1: The bidiagonal matrix has column dimension M = N + 1.
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
56 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
57 * D (input/output) REAL array, dimension ( N )
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
58 * On entry D contains the main diagonal of the bidiagonal
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
59 * matrix. On exit D, if INFO = 0, contains its singular values.
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
60 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
61 * E (input) REAL array, dimension ( M-1 )
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
62 * Contains the subdiagonal entries of the bidiagonal matrix.
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
63 * On exit, E has been destroyed.
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
64 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
65 * U (output) REAL array,
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
66 * dimension ( LDU, SMLSIZ ) if ICOMPQ = 1, and not referenced
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
67 * if ICOMPQ = 0. If ICOMPQ = 1, on exit, U contains the left
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
68 * singular vector matrices of all subproblems at the bottom
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
69 * level.
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
70 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
71 * LDU (input) INTEGER, LDU = > N.
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
72 * The leading dimension of arrays U, VT, DIFL, DIFR, POLES,
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
73 * GIVNUM, and Z.
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
74 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
75 * VT (output) REAL array,
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
76 * dimension ( LDU, SMLSIZ+1 ) if ICOMPQ = 1, and not referenced
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
77 * if ICOMPQ = 0. If ICOMPQ = 1, on exit, VT' contains the right
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
78 * singular vector matrices of all subproblems at the bottom
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
79 * level.
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
80 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
81 * K (output) INTEGER array, dimension ( N )
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
82 * if ICOMPQ = 1 and dimension 1 if ICOMPQ = 0.
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
83 * If ICOMPQ = 1, on exit, K(I) is the dimension of the I-th
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
84 * secular equation on the computation tree.
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
85 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
86 * DIFL (output) REAL array, dimension ( LDU, NLVL ),
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
87 * where NLVL = floor(log_2 (N/SMLSIZ))).
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
88 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
89 * DIFR (output) REAL array,
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
90 * dimension ( LDU, 2 * NLVL ) if ICOMPQ = 1 and
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
91 * dimension ( N ) if ICOMPQ = 0.
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
92 * If ICOMPQ = 1, on exit, DIFL(1:N, I) and DIFR(1:N, 2 * I - 1)
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
93 * record distances between singular values on the I-th
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
94 * level and singular values on the (I -1)-th level, and
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
95 * DIFR(1:N, 2 * I ) contains the normalizing factors for
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
96 * the right singular vector matrix. See SLASD8 for details.
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
97 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
98 * Z (output) REAL array,
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
99 * dimension ( LDU, NLVL ) if ICOMPQ = 1 and
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
100 * dimension ( N ) if ICOMPQ = 0.
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
101 * The first K elements of Z(1, I) contain the components of
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
102 * the deflation-adjusted updating row vector for subproblems
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
103 * on the I-th level.
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
104 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
105 * POLES (output) REAL array,
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
106 * dimension ( LDU, 2 * NLVL ) if ICOMPQ = 1, and not referenced
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
107 * if ICOMPQ = 0. If ICOMPQ = 1, on exit, POLES(1, 2*I - 1) and
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
108 * POLES(1, 2*I) contain the new and old singular values
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
109 * involved in the secular equations on the I-th level.
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
110 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
111 * GIVPTR (output) INTEGER array,
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
112 * dimension ( N ) if ICOMPQ = 1, and not referenced if
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
113 * ICOMPQ = 0. If ICOMPQ = 1, on exit, GIVPTR( I ) records
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
114 * the number of Givens rotations performed on the I-th
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
115 * problem on the computation tree.
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
116 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
117 * GIVCOL (output) INTEGER array,
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
118 * dimension ( LDGCOL, 2 * NLVL ) if ICOMPQ = 1, and not
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
119 * referenced if ICOMPQ = 0. If ICOMPQ = 1, on exit, for each I,
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
120 * GIVCOL(1, 2 *I - 1) and GIVCOL(1, 2 *I) record the locations
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
121 * of Givens rotations performed on the I-th level on the
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
122 * computation tree.
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
123 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
124 * LDGCOL (input) INTEGER, LDGCOL = > N.
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
125 * The leading dimension of arrays GIVCOL and PERM.
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
126 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
127 * PERM (output) INTEGER array, dimension ( LDGCOL, NLVL )
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
128 * if ICOMPQ = 1, and not referenced
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
129 * if ICOMPQ = 0. If ICOMPQ = 1, on exit, PERM(1, I) records
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
130 * permutations done on the I-th level of the computation tree.
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
131 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
132 * GIVNUM (output) REAL array,
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
133 * dimension ( LDU, 2 * NLVL ) if ICOMPQ = 1, and not
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
134 * referenced if ICOMPQ = 0. If ICOMPQ = 1, on exit, for each I,
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
135 * GIVNUM(1, 2 *I - 1) and GIVNUM(1, 2 *I) record the C- and S-
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
136 * values of Givens rotations performed on the I-th level on
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
137 * the computation tree.
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
138 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
139 * C (output) REAL array,
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
140 * dimension ( N ) if ICOMPQ = 1, and dimension 1 if ICOMPQ = 0.
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
141 * If ICOMPQ = 1 and the I-th subproblem is not square, on exit,
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
142 * C( I ) contains the C-value of a Givens rotation related to
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
143 * the right null space of the I-th subproblem.
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
144 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
145 * S (output) REAL array, dimension ( N ) if
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
146 * ICOMPQ = 1, and dimension 1 if ICOMPQ = 0. If ICOMPQ = 1
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
147 * and the I-th subproblem is not square, on exit, S( I )
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
148 * contains the S-value of a Givens rotation related to
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
149 * the right null space of the I-th subproblem.
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
150 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
151 * WORK (workspace) REAL array, dimension
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
152 * (6 * N + (SMLSIZ + 1)*(SMLSIZ + 1)).
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
153 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
154 * IWORK (workspace) INTEGER array, dimension (7*N).
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
155 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
156 * INFO (output) INTEGER
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
157 * = 0: successful exit.
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
158 * < 0: if INFO = -i, the i-th argument had an illegal value.
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
159 * > 0: if INFO = 1, an singular value did not converge
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
160 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
161 * Further Details
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
162 * ===============
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
163 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
164 * Based on contributions by
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
165 * Ming Gu and Huan Ren, Computer Science Division, University of
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
166 * California at Berkeley, USA
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
167 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
168 * =====================================================================
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
169 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
170 * .. Parameters ..
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
171 REAL ZERO, ONE
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
172 PARAMETER ( ZERO = 0.0E+0, ONE = 1.0E+0 )
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
173 * ..
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
174 * .. Local Scalars ..
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
175 INTEGER I, I1, IC, IDXQ, IDXQI, IM1, INODE, ITEMP, IWK,
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
176 $ J, LF, LL, LVL, LVL2, M, NCC, ND, NDB1, NDIML,
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
177 $ NDIMR, NL, NLF, NLP1, NLVL, NR, NRF, NRP1, NRU,
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
178 $ NWORK1, NWORK2, SMLSZP, SQREI, VF, VFI, VL, VLI
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
179 REAL ALPHA, BETA
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
180 * ..
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
181 * .. External Subroutines ..
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
182 EXTERNAL SCOPY, SLASD6, SLASDQ, SLASDT, SLASET, XERBLA
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
183 * ..
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
184 * .. Executable Statements ..
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
185 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
186 * Test the input parameters.
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
187 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
188 INFO = 0
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
189 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
190 IF( ( ICOMPQ.LT.0 ) .OR. ( ICOMPQ.GT.1 ) ) THEN
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
191 INFO = -1
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
192 ELSE IF( SMLSIZ.LT.3 ) THEN
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
193 INFO = -2
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
194 ELSE IF( N.LT.0 ) THEN
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
195 INFO = -3
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
196 ELSE IF( ( SQRE.LT.0 ) .OR. ( SQRE.GT.1 ) ) THEN
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
197 INFO = -4
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
198 ELSE IF( LDU.LT.( N+SQRE ) ) THEN
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
199 INFO = -8
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
200 ELSE IF( LDGCOL.LT.N ) THEN
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
201 INFO = -17
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
202 END IF
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
203 IF( INFO.NE.0 ) THEN
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
204 CALL XERBLA( 'SLASDA', -INFO )
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
205 RETURN
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
206 END IF
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
207 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
208 M = N + SQRE
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
209 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
210 * If the input matrix is too small, call SLASDQ to find the SVD.
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
211 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
212 IF( N.LE.SMLSIZ ) THEN
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
213 IF( ICOMPQ.EQ.0 ) THEN
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
214 CALL SLASDQ( 'U', SQRE, N, 0, 0, 0, D, E, VT, LDU, U, LDU,
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
215 $ U, LDU, WORK, INFO )
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
216 ELSE
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
217 CALL SLASDQ( 'U', SQRE, N, M, N, 0, D, E, VT, LDU, U, LDU,
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
218 $ U, LDU, WORK, INFO )
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
219 END IF
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
220 RETURN
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
221 END IF
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
222 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
223 * Book-keeping and set up the computation tree.
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
224 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
225 INODE = 1
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
226 NDIML = INODE + N
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
227 NDIMR = NDIML + N
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
228 IDXQ = NDIMR + N
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
229 IWK = IDXQ + N
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
230 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
231 NCC = 0
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
232 NRU = 0
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
233 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
234 SMLSZP = SMLSIZ + 1
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
235 VF = 1
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
236 VL = VF + M
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
237 NWORK1 = VL + M
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
238 NWORK2 = NWORK1 + SMLSZP*SMLSZP
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
239 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
240 CALL SLASDT( N, NLVL, ND, IWORK( INODE ), IWORK( NDIML ),
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
241 $ IWORK( NDIMR ), SMLSIZ )
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
242 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
243 * for the nodes on bottom level of the tree, solve
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
244 * their subproblems by SLASDQ.
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
245 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
246 NDB1 = ( ND+1 ) / 2
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
247 DO 30 I = NDB1, ND
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
248 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
249 * IC : center row of each node
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
250 * NL : number of rows of left subproblem
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
251 * NR : number of rows of right subproblem
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
252 * NLF: starting row of the left subproblem
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
253 * NRF: starting row of the right subproblem
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
254 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
255 I1 = I - 1
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
256 IC = IWORK( INODE+I1 )
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
257 NL = IWORK( NDIML+I1 )
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
258 NLP1 = NL + 1
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
259 NR = IWORK( NDIMR+I1 )
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
260 NLF = IC - NL
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
261 NRF = IC + 1
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
262 IDXQI = IDXQ + NLF - 2
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
263 VFI = VF + NLF - 1
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
264 VLI = VL + NLF - 1
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
265 SQREI = 1
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
266 IF( ICOMPQ.EQ.0 ) THEN
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
267 CALL SLASET( 'A', NLP1, NLP1, ZERO, ONE, WORK( NWORK1 ),
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
268 $ SMLSZP )
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
269 CALL SLASDQ( 'U', SQREI, NL, NLP1, NRU, NCC, D( NLF ),
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
270 $ E( NLF ), WORK( NWORK1 ), SMLSZP,
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
271 $ WORK( NWORK2 ), NL, WORK( NWORK2 ), NL,
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
272 $ WORK( NWORK2 ), INFO )
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
273 ITEMP = NWORK1 + NL*SMLSZP
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
274 CALL SCOPY( NLP1, WORK( NWORK1 ), 1, WORK( VFI ), 1 )
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
275 CALL SCOPY( NLP1, WORK( ITEMP ), 1, WORK( VLI ), 1 )
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
276 ELSE
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
277 CALL SLASET( 'A', NL, NL, ZERO, ONE, U( NLF, 1 ), LDU )
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
278 CALL SLASET( 'A', NLP1, NLP1, ZERO, ONE, VT( NLF, 1 ), LDU )
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
279 CALL SLASDQ( 'U', SQREI, NL, NLP1, NL, NCC, D( NLF ),
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
280 $ E( NLF ), VT( NLF, 1 ), LDU, U( NLF, 1 ), LDU,
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
281 $ U( NLF, 1 ), LDU, WORK( NWORK1 ), INFO )
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
282 CALL SCOPY( NLP1, VT( NLF, 1 ), 1, WORK( VFI ), 1 )
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
283 CALL SCOPY( NLP1, VT( NLF, NLP1 ), 1, WORK( VLI ), 1 )
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
284 END IF
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
285 IF( INFO.NE.0 ) THEN
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
286 RETURN
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
287 END IF
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
288 DO 10 J = 1, NL
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
289 IWORK( IDXQI+J ) = J
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
290 10 CONTINUE
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
291 IF( ( I.EQ.ND ) .AND. ( SQRE.EQ.0 ) ) THEN
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
292 SQREI = 0
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
293 ELSE
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
294 SQREI = 1
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
295 END IF
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
296 IDXQI = IDXQI + NLP1
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
297 VFI = VFI + NLP1
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
298 VLI = VLI + NLP1
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
299 NRP1 = NR + SQREI
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
300 IF( ICOMPQ.EQ.0 ) THEN
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
301 CALL SLASET( 'A', NRP1, NRP1, ZERO, ONE, WORK( NWORK1 ),
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
302 $ SMLSZP )
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
303 CALL SLASDQ( 'U', SQREI, NR, NRP1, NRU, NCC, D( NRF ),
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
304 $ E( NRF ), WORK( NWORK1 ), SMLSZP,
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
305 $ WORK( NWORK2 ), NR, WORK( NWORK2 ), NR,
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
306 $ WORK( NWORK2 ), INFO )
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
307 ITEMP = NWORK1 + ( NRP1-1 )*SMLSZP
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
308 CALL SCOPY( NRP1, WORK( NWORK1 ), 1, WORK( VFI ), 1 )
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
309 CALL SCOPY( NRP1, WORK( ITEMP ), 1, WORK( VLI ), 1 )
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
310 ELSE
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
311 CALL SLASET( 'A', NR, NR, ZERO, ONE, U( NRF, 1 ), LDU )
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
312 CALL SLASET( 'A', NRP1, NRP1, ZERO, ONE, VT( NRF, 1 ), LDU )
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
313 CALL SLASDQ( 'U', SQREI, NR, NRP1, NR, NCC, D( NRF ),
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
314 $ E( NRF ), VT( NRF, 1 ), LDU, U( NRF, 1 ), LDU,
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
315 $ U( NRF, 1 ), LDU, WORK( NWORK1 ), INFO )
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
316 CALL SCOPY( NRP1, VT( NRF, 1 ), 1, WORK( VFI ), 1 )
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
317 CALL SCOPY( NRP1, VT( NRF, NRP1 ), 1, WORK( VLI ), 1 )
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
318 END IF
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
319 IF( INFO.NE.0 ) THEN
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
320 RETURN
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
321 END IF
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
322 DO 20 J = 1, NR
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
323 IWORK( IDXQI+J ) = J
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
324 20 CONTINUE
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
325 30 CONTINUE
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
326 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
327 * Now conquer each subproblem bottom-up.
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
328 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
329 J = 2**NLVL
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
330 DO 50 LVL = NLVL, 1, -1
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
331 LVL2 = LVL*2 - 1
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
332 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
333 * Find the first node LF and last node LL on
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
334 * the current level LVL.
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
335 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
336 IF( LVL.EQ.1 ) THEN
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
337 LF = 1
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
338 LL = 1
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
339 ELSE
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
340 LF = 2**( LVL-1 )
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
341 LL = 2*LF - 1
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
342 END IF
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
343 DO 40 I = LF, LL
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
344 IM1 = I - 1
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
345 IC = IWORK( INODE+IM1 )
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
346 NL = IWORK( NDIML+IM1 )
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
347 NR = IWORK( NDIMR+IM1 )
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
348 NLF = IC - NL
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
349 NRF = IC + 1
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
350 IF( I.EQ.LL ) THEN
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
351 SQREI = SQRE
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
352 ELSE
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
353 SQREI = 1
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
354 END IF
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
355 VFI = VF + NLF - 1
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
356 VLI = VL + NLF - 1
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
357 IDXQI = IDXQ + NLF - 1
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
358 ALPHA = D( IC )
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
359 BETA = E( IC )
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
360 IF( ICOMPQ.EQ.0 ) THEN
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
361 CALL SLASD6( ICOMPQ, NL, NR, SQREI, D( NLF ),
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
362 $ WORK( VFI ), WORK( VLI ), ALPHA, BETA,
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
363 $ IWORK( IDXQI ), PERM, GIVPTR( 1 ), GIVCOL,
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
364 $ LDGCOL, GIVNUM, LDU, POLES, DIFL, DIFR, Z,
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
365 $ K( 1 ), C( 1 ), S( 1 ), WORK( NWORK1 ),
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
366 $ IWORK( IWK ), INFO )
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
367 ELSE
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
368 J = J - 1
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
369 CALL SLASD6( ICOMPQ, NL, NR, SQREI, D( NLF ),
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
370 $ WORK( VFI ), WORK( VLI ), ALPHA, BETA,
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
371 $ IWORK( IDXQI ), PERM( NLF, LVL ),
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
372 $ GIVPTR( J ), GIVCOL( NLF, LVL2 ), LDGCOL,
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
373 $ GIVNUM( NLF, LVL2 ), LDU,
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
374 $ POLES( NLF, LVL2 ), DIFL( NLF, LVL ),
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
375 $ DIFR( NLF, LVL2 ), Z( NLF, LVL ), K( J ),
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
376 $ C( J ), S( J ), WORK( NWORK1 ),
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
377 $ IWORK( IWK ), INFO )
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
378 END IF
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
379 IF( INFO.NE.0 ) THEN
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
380 RETURN
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
381 END IF
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
382 40 CONTINUE
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
383 50 CONTINUE
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
384 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
385 RETURN
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
386 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
387 * End of SLASDA
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
388 *
82be108cc558 First attempt at single precision tyeps
David Bateman <dbateman@free.fr>
parents:
diff changeset
389 END