Visible to Intel only — GUID: GUID-152DBBE2-356D-476C-A234-98C420E2055B
Visible to Intel only — GUID: GUID-152DBBE2-356D-476C-A234-98C420E2055B
?syswapr
Applies an elementary permutation on the rows and columns of a symmetric matrix.
Syntax
call ssyswapr( uplo, n, a, lda, i1, i2 )
call dsyswapr( uplo, n, a, lda, i1, i2 )
call csyswapr( uplo, n, a, lda, i1, i2 )
call zsyswapr( uplo, n, a, lda, i1, i2 )
call syswapr( a,i1,i2[,uplo] )
Include Files
- mkl.fi, lapack.f90
Description
The routine applies an elementary permutation on the rows and columns of a symmetric matrix.
Input Parameters
The data types are given for the Fortran interface.
- uplo
-
CHARACTER*1. Must be 'U' or 'L'.
Indicates how the input matrix A has been factored:
If uplo = 'U', the array a stores the upper triangular factor U of the factorization A = U*D*UT.
If uplo = 'L', the array a stores the lower triangular factor L of the factorization A = L*D*LT.
- n
-
INTEGER. The order of matrix A; n≥ 0.
- nrhs
-
INTEGER. The number of right-hand sides; nrhs≥ 0.
- a
-
REAL for ssyswapr
DOUBLE PRECISION for dsyswapr
COMPLEX for csyswapr
DOUBLE COMPLEX for zsyswapr
Array of size (lda, n).
The array a contains the block diagonal matrix D and the multipliers used to obtain the factor U or L as computed by ?sytrf.
- lda
-
INTEGER. The leading dimension of the array a. lda≥max(1,n).
- i1
-
INTEGER. Index of the first row to swap.
- i2
-
INTEGER. Index of the second row to swap.
Output Parameters
- a
-
If info = 0, the symmetric inverse of the original matrix.
If info = 'U', the upper triangular part of the inverse is formed and the part of A below the diagonal is not referenced.
If info = 'L', the lower triangular part of the inverse is formed and the part of A above the diagonal is not referenced.
LAPACK 95 Interface Notes
Routines in Fortran 95 interface have fewer arguments in the calling sequence than their FORTRAN 77 counterparts. For general conventions applied to skip redundant or reconstructible arguments, see LAPACK 95 Interface Conventions.
Specific details for the routine syswapr interface are as follows:
- a
-
Holds the matrix A of size (n, n).
- i1
-
Holds the index for swap.
- i2
-
Holds the index for swap.
- uplo
-
Indicates how the matrix A has been factored. Must be 'U' or 'L'.