DSYSWAPR(3) LAPACK routine of NEC Numeric Library Collection DSYSWAPR(3) NAME DSYSWAPR SYNOPSIS SUBROUTINE DSYSWAPR (UPLO, N, A, LDA, I1, I2) PURPOSE DSYSWAPR applies an elementary permutation on the rows and the columns of a symmetric matrix. ARGUMENTS UPLO (input) 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. N (input) N is INTEGER The order of the matrix A. N >= 0. A (input/output) A is DOUBLE PRECISION 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 DSYTRF. 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. LDA (input) LDA is INTEGER The leading dimension of the array A. LDA >= max(1,N). I1 (input) I1 is INTEGER Index of the first row to swap I2 (input) I2 is INTEGER Index of the second row to swap LAPACK routine 31 October 2017 DSYSWAPR(3)