LAPACK 3.11.0
LAPACK: Linear Algebra PACKage
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zlapmt.f
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1*> \brief \b ZLAPMT performs a forward or backward permutation of the columns of a matrix.
2*
3* =========== DOCUMENTATION ===========
4*
5* Online html documentation available at
6* http://www.netlib.org/lapack/explore-html/
7*
8*> \htmlonly
9*> Download ZLAPMT + dependencies
10*> <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/zlapmt.f">
11*> [TGZ]</a>
12*> <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/zlapmt.f">
13*> [ZIP]</a>
14*> <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/zlapmt.f">
15*> [TXT]</a>
16*> \endhtmlonly
17*
18* Definition:
19* ===========
20*
21* SUBROUTINE ZLAPMT( 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* COMPLEX*16 X( LDX, * )
30* ..
31*
32*
33*> \par Purpose:
34* =============
35*>
36*> \verbatim
37*>
38*> ZLAPMT rearranges the columns of the M by N matrix X as specified
39*> by the permutation K(1),K(2),...,K(N) of the integers 1,...,N.
40*> If FORWRD = .TRUE., forward permutation:
41*>
42*> X(*,K(J)) is moved X(*,J) for J = 1,2,...,N.
43*>
44*> If FORWRD = .FALSE., backward permutation:
45*>
46*> X(*,J) is moved to X(*,K(J)) for J = 1,2,...,N.
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 COMPLEX*16 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 (N)
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*> \ingroup complex16OTHERauxiliary
101*
102* =====================================================================
103 SUBROUTINE zlapmt( FORWRD, M, N, X, LDX, K )
104*
105* -- LAPACK auxiliary routine --
106* -- LAPACK is a software package provided by Univ. of Tennessee, --
107* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
108*
109* .. Scalar Arguments ..
110 LOGICAL FORWRD
111 INTEGER LDX, M, N
112* ..
113* .. Array Arguments ..
114 INTEGER K( * )
115 COMPLEX*16 X( LDX, * )
116* ..
117*
118* =====================================================================
119*
120* .. Local Scalars ..
121 INTEGER I, II, IN, J
122 COMPLEX*16 TEMP
123* ..
124* .. Executable Statements ..
125*
126 IF( n.LE.1 )
127 $ RETURN
128*
129 DO 10 i = 1, n
130 k( i ) = -k( i )
131 10 CONTINUE
132*
133 IF( forwrd ) THEN
134*
135* Forward permutation
136*
137 DO 50 i = 1, n
138*
139 IF( k( i ).GT.0 )
140 $ GO TO 40
141*
142 j = i
143 k( j ) = -k( j )
144 in = k( j )
145*
146 20 CONTINUE
147 IF( k( in ).GT.0 )
148 $ GO TO 40
149*
150 DO 30 ii = 1, m
151 temp = x( ii, j )
152 x( ii, j ) = x( ii, in )
153 x( ii, in ) = temp
154 30 CONTINUE
155*
156 k( in ) = -k( in )
157 j = in
158 in = k( in )
159 GO TO 20
160*
161 40 CONTINUE
162*
163 50 CONTINUE
164*
165 ELSE
166*
167* Backward permutation
168*
169 DO 90 i = 1, n
170*
171 IF( k( i ).GT.0 )
172 $ GO TO 80
173*
174 k( i ) = -k( i )
175 j = k( i )
176 60 CONTINUE
177 IF( j.EQ.i )
178 $ GO TO 80
179*
180 DO 70 ii = 1, m
181 temp = x( ii, i )
182 x( ii, i ) = x( ii, j )
183 x( ii, j ) = temp
184 70 CONTINUE
185*
186 k( j ) = -k( j )
187 j = k( j )
188 GO TO 60
189*
190 80 CONTINUE
191*
192 90 CONTINUE
193*
194 END IF
195*
196 RETURN
197*
198* End of ZLAPMT
199*
200 END
subroutine zlapmt(FORWRD, M, N, X, LDX, K)
ZLAPMT performs a forward or backward permutation of the columns of a matrix.
Definition: zlapmt.f:104