LAPACK  3.6.1 LAPACK: Linear Algebra PACKage
 subroutine zsyswapr ( character UPLO, integer N, complex*16, dimension( lda, n ) A, integer LDA, integer I1, integer I2 )

ZSYSWAPR

Purpose:
``` ZSYSWAPR applies an elementary permutation on the rows and the columns of
a symmetric matrix.```
Parameters
 [in] UPLO ``` UPLO is CHARACTER*1 Specifies whether the details of the factorization are stored as an upper or lower triangular matrix. = 'U': Upper triangular, form is A = U*D*U**T; = 'L': Lower triangular, form is A = L*D*L**T.``` [in] N ``` N is INTEGER The order of the matrix A. N >= 0.``` [in,out] A ``` A is COMPLEX*16 array, dimension (LDA,N) On entry, the NB diagonal matrix D and the multipliers used to obtain the factor U or L as computed by ZSYTRF. On exit, if INFO = 0, the (symmetric) inverse of the original matrix. If UPLO = 'U', the upper triangular part of the inverse is formed and the part of A below the diagonal is not referenced; if UPLO = 'L' the lower triangular part of the inverse is formed and the part of A above the diagonal is not referenced.``` [in] LDA ``` LDA is INTEGER The leading dimension of the array A. LDA >= max(1,N).``` [in] I1 ``` I1 is INTEGER Index of the first row to swap``` [in] I2 ``` I2 is INTEGER Index of the second row to swap```
Date
November 2011

Definition at line 104 of file zsyswapr.f.

104 *
105 * -- LAPACK auxiliary routine (version 3.4.0) --
106 * -- LAPACK is a software package provided by Univ. of Tennessee, --
107 * -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
108 * November 2011
109 *
110 * .. Scalar Arguments ..
111  CHARACTER uplo
112  INTEGER i1, i2, lda, n
113 * ..
114 * .. Array Arguments ..
115  COMPLEX*16 a( lda, n )
116 *
117 * =====================================================================
118 *
119 * ..
120 * .. Local Scalars ..
121  LOGICAL upper
122  INTEGER i
123  COMPLEX*16 tmp
124 *
125 * .. External Functions ..
126  LOGICAL lsame
127  EXTERNAL lsame
128 * ..
129 * .. External Subroutines ..
130  EXTERNAL zswap
131 * ..
132 * .. Executable Statements ..
133 *
134  upper = lsame( uplo, 'U' )
135  IF (upper) THEN
136 *
137 * UPPER
138 * first swap
139 * - swap column I1 and I2 from I1 to I1-1
140  CALL zswap( i1-1, a(1,i1), 1, a(1,i2), 1 )
141 *
142 * second swap :
143 * - swap A(I1,I1) and A(I2,I2)
144 * - swap row I1 from I1+1 to I2-1 with col I2 from I1+1 to I2-1
145  tmp=a(i1,i1)
146  a(i1,i1)=a(i2,i2)
147  a(i2,i2)=tmp
148 *
149  DO i=1,i2-i1-1
150  tmp=a(i1,i1+i)
151  a(i1,i1+i)=a(i1+i,i2)
152  a(i1+i,i2)=tmp
153  END DO
154 *
155 * third swap
156 * - swap row I1 and I2 from I2+1 to N
157  DO i=i2+1,n
158  tmp=a(i1,i)
159  a(i1,i)=a(i2,i)
160  a(i2,i)=tmp
161  END DO
162 *
163  ELSE
164 *
165 * LOWER
166 * first swap
167 * - swap row I1 and I2 from I1 to I1-1
168  CALL zswap( i1-1, a(i1,1), lda, a(i2,1), lda )
169 *
170 * second swap :
171 * - swap A(I1,I1) and A(I2,I2)
172 * - swap col I1 from I1+1 to I2-1 with row I2 from I1+1 to I2-1
173  tmp=a(i1,i1)
174  a(i1,i1)=a(i2,i2)
175  a(i2,i2)=tmp
176 *
177  DO i=1,i2-i1-1
178  tmp=a(i1+i,i1)
179  a(i1+i,i1)=a(i2,i1+i)
180  a(i2,i1+i)=tmp
181  END DO
182 *
183 * third swap
184 * - swap col I1 and I2 from I2+1 to N
185  DO i=i2+1,n
186  tmp=a(i,i1)
187  a(i,i1)=a(i,i2)
188  a(i,i2)=tmp
189  END DO
190 *
191  ENDIF
subroutine zswap(N, ZX, INCX, ZY, INCY)
ZSWAP
Definition: zswap.f:52
logical function lsame(CA, CB)
LSAME
Definition: lsame.f:55

Here is the call graph for this function:

Here is the caller graph for this function: