 LAPACK 3.11.0 LAPACK: Linear Algebra PACKage
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## ◆ zheswapr()

 subroutine zheswapr ( character UPLO, integer N, complex*16, dimension( lda, n ) A, integer LDA, integer I1, integer I2 )

ZHESWAPR applies an elementary permutation on the rows and columns of a Hermitian matrix.

Purpose:
``` ZHESWAPR applies an elementary permutation on the rows and the columns of
a hermitian 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 CSYTRF. 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```

Definition at line 101 of file zheswapr.f.

102*
103* -- LAPACK auxiliary routine --
104* -- LAPACK is a software package provided by Univ. of Tennessee, --
105* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
106*
107* .. Scalar Arguments ..
108 CHARACTER UPLO
109 INTEGER I1, I2, LDA, N
110* ..
111* .. Array Arguments ..
112 COMPLEX*16 A( LDA, N )
113*
114* =====================================================================
115*
116* ..
117* .. Local Scalars ..
118 LOGICAL UPPER
119 INTEGER I
120 COMPLEX*16 TMP
121*
122* .. External Functions ..
123 LOGICAL LSAME
124 EXTERNAL lsame
125* ..
126* .. External Subroutines ..
127 EXTERNAL zswap
128* ..
129* .. Executable Statements ..
130*
131 upper = lsame( uplo, 'U' )
132 IF (upper) THEN
133*
134* UPPER
135* first swap
136* - swap column I1 and I2 from I1 to I1-1
137 CALL zswap( i1-1, a(1,i1), 1, a(1,i2), 1 )
138*
139* second swap :
140* - swap A(I1,I1) and A(I2,I2)
141* - swap row I1 from I1+1 to I2-1 with col I2 from I1+1 to I2-1
142* - swap A(I2,I1) and A(I1,I2)
143
144 tmp=a(i1,i1)
145 a(i1,i1)=a(i2,i2)
146 a(i2,i2)=tmp
147*
148 DO i=1,i2-i1-1
149 tmp=a(i1,i1+i)
150 a(i1,i1+i)=dconjg(a(i1+i,i2))
151 a(i1+i,i2)=dconjg(tmp)
152 END DO
153*
154 a(i1,i2)=dconjg(a(i1,i2))
155
156*
157* third swap
158* - swap row I1 and I2 from I2+1 to N
159 DO i=i2+1,n
160 tmp=a(i1,i)
161 a(i1,i)=a(i2,i)
162 a(i2,i)=tmp
163 END DO
164*
165 ELSE
166*
167* LOWER
168* first swap
169* - swap row I1 and I2 from 1 to I1-1
170 CALL zswap ( i1-1, a(i1,1), lda, a(i2,1), lda )
171*
172* second swap :
173* - swap A(I1,I1) and A(I2,I2)
174* - swap col I1 from I1+1 to I2-1 with row I2 from I1+1 to I2-1
175* - swap A(I2,I1) and A(I1,I2)
176
177 tmp=a(i1,i1)
178 a(i1,i1)=a(i2,i2)
179 a(i2,i2)=tmp
180*
181 DO i=1,i2-i1-1
182 tmp=a(i1+i,i1)
183 a(i1+i,i1)=dconjg(a(i2,i1+i))
184 a(i2,i1+i)=dconjg(tmp)
185 END DO
186*
187 a(i2,i1)=dconjg(a(i2,i1))
188*
189* third swap
190* - swap col I1 and I2 from I2+1 to N
191 DO i=i2+1,n
192 tmp=a(i,i1)
193 a(i,i1)=a(i,i2)
194 a(i,i2)=tmp
195 END DO
196*
197 ENDIF
198
logical function lsame(CA, CB)
LSAME
Definition: lsame.f:53
subroutine zswap(N, ZX, INCX, ZY, INCY)
ZSWAP
Definition: zswap.f:81
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