LAPACK  3.6.1 LAPACK: Linear Algebra PACKage
slapmr.f
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1 *> \brief \b SLAPMR rearranges rows of a matrix as specified by a permutation vector.
2 *
3 * =========== DOCUMENTATION ===========
4 *
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17 *
18 * Definition:
19 * ===========
20 *
21 * SUBROUTINE SLAPMR( FORWRD, M, N, X, LDX, K )
22 *
23 * .. Scalar Arguments ..
24 * LOGICAL FORWRD
25 * INTEGER LDX, M, N
26 * ..
27 * .. Array Arguments ..
28 * INTEGER K( * )
29 * REAL X( LDX, * )
30 * ..
31 *
32 *
33 *> \par Purpose:
34 * =============
35 *>
36 *> \verbatim
37 *>
38 *> SLAPMR rearranges the rows of the M by N matrix X as specified
39 *> by the permutation K(1),K(2),...,K(M) of the integers 1,...,M.
40 *> If FORWRD = .TRUE., forward permutation:
41 *>
42 *> X(K(I),*) is moved X(I,*) for I = 1,2,...,M.
43 *>
44 *> If FORWRD = .FALSE., backward permutation:
45 *>
46 *> X(I,*) is moved to X(K(I),*) for I = 1,2,...,M.
47 *> \endverbatim
48 *
49 * Arguments:
50 * ==========
51 *
52 *> \param[in] FORWRD
53 *> \verbatim
54 *> FORWRD is LOGICAL
55 *> = .TRUE., forward permutation
56 *> = .FALSE., backward permutation
57 *> \endverbatim
58 *>
59 *> \param[in] M
60 *> \verbatim
61 *> M is INTEGER
62 *> The number of rows of the matrix X. M >= 0.
63 *> \endverbatim
64 *>
65 *> \param[in] N
66 *> \verbatim
67 *> N is INTEGER
68 *> The number of columns of the matrix X. N >= 0.
69 *> \endverbatim
70 *>
71 *> \param[in,out] X
72 *> \verbatim
73 *> X is REAL array, dimension (LDX,N)
74 *> On entry, the M by N matrix X.
75 *> On exit, X contains the permuted matrix X.
76 *> \endverbatim
77 *>
78 *> \param[in] LDX
79 *> \verbatim
80 *> LDX is INTEGER
81 *> The leading dimension of the array X, LDX >= MAX(1,M).
82 *> \endverbatim
83 *>
84 *> \param[in,out] K
85 *> \verbatim
86 *> K is INTEGER array, dimension (M)
87 *> On entry, K contains the permutation vector. K is used as
88 *> internal workspace, but reset to its original value on
89 *> output.
90 *> \endverbatim
91 *
92 * Authors:
93 * ========
94 *
95 *> \author Univ. of Tennessee
96 *> \author Univ. of California Berkeley
97 *> \author Univ. of Colorado Denver
98 *> \author NAG Ltd.
99 *
100 *> \date September 2012
101 *
102 *> \ingroup realOTHERauxiliary
103 *
104 * =====================================================================
105  SUBROUTINE slapmr( FORWRD, M, N, X, LDX, K )
106 *
107 * -- LAPACK auxiliary routine (version 3.4.2) --
108 * -- LAPACK is a software package provided by Univ. of Tennessee, --
109 * -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
110 * September 2012
111 *
112 * .. Scalar Arguments ..
113  LOGICAL FORWRD
114  INTEGER LDX, M, N
115 * ..
116 * .. Array Arguments ..
117  INTEGER K( * )
118  REAL X( ldx, * )
119 * ..
120 *
121 * =====================================================================
122 *
123 * .. Local Scalars ..
124  INTEGER I, IN, J, JJ
125  REAL TEMP
126 * ..
127 * .. Executable Statements ..
128 *
129  IF( m.LE.1 )
130  \$ RETURN
131 *
132  DO 10 i = 1, m
133  k( i ) = -k( i )
134  10 CONTINUE
135 *
136  IF( forwrd ) THEN
137 *
138 * Forward permutation
139 *
140  DO 50 i = 1, m
141 *
142  IF( k( i ).GT.0 )
143  \$ GO TO 40
144 *
145  j = i
146  k( j ) = -k( j )
147  in = k( j )
148 *
149  20 CONTINUE
150  IF( k( in ).GT.0 )
151  \$ GO TO 40
152 *
153  DO 30 jj = 1, n
154  temp = x( j, jj )
155  x( j, jj ) = x( in, jj )
156  x( in, jj ) = temp
157  30 CONTINUE
158 *
159  k( in ) = -k( in )
160  j = in
161  in = k( in )
162  GO TO 20
163 *
164  40 CONTINUE
165 *
166  50 CONTINUE
167 *
168  ELSE
169 *
170 * Backward permutation
171 *
172  DO 90 i = 1, m
173 *
174  IF( k( i ).GT.0 )
175  \$ GO TO 80
176 *
177  k( i ) = -k( i )
178  j = k( i )
179  60 CONTINUE
180  IF( j.EQ.i )
181  \$ GO TO 80
182 *
183  DO 70 jj = 1, n
184  temp = x( i, jj )
185  x( i, jj ) = x( j, jj )
186  x( j, jj ) = temp
187  70 CONTINUE
188 *
189  k( j ) = -k( j )
190  j = k( j )
191  GO TO 60
192 *
193  80 CONTINUE
194 *
195  90 CONTINUE
196 *
197  END IF
198 *
199  RETURN
200 *
201 * End of ZLAPMT
202 *
203  END
204
subroutine slapmr(FORWRD, M, N, X, LDX, K)
SLAPMR rearranges rows of a matrix as specified by a permutation vector.
Definition: slapmr.f:106