?laswp

Performs a series of row interchanges on a general rectangular matrix.

Syntax

call slaswp( n, a, lda, k1, k2, ipiv, incx )

call dlaswp( n, a, lda, k1, k2, ipiv, incx )

call claswp( n, a, lda, k1, k2, ipiv, incx )

call zlaswp( n, a, lda, k1, k2, ipiv, incx )

Include Files

The FORTRAN 77 interfaces are specified in the mkl_lapack.fi include file (to be used in Fortran programs) and in the mkl_lapack.h include file (to be used in C programs).

Description

The routine performs a series of row interchanges on the matrix A. One row interchange is initiated for each of rows k1 through k2 of A.

Input Parameters

n

INTEGER. The number of columns of the matrix A.

a

REAL for slaswp

DOUBLE PRECISION for dlaswp

COMPLEX for claswp

DOUBLE COMPLEX for zlaswp.

Array, DIMENSION (lda, n).

On entry, the matrix of column dimension n to which the row interchanges will be applied.

lda

INTEGER. The leading dimension of the array a.

k1

INTEGER. The first element of ipiv for which a row interchange will be done.

k2

INTEGER. The last element of ipiv for which a row interchange will be done.

ipiv

INTEGER.

Array, DIMENSION (k2*|incx|).

The vector of pivot indices. Only the elements in positions k1 through k2 of ipiv are accessed.

ipiv(k) = l implies rows k and l are to be interchanged.

incx

INTEGER. The increment between successive values of ipiv. If ipiv is negative, the pivots are applied in reverse order.

Output Parameters

a: On exit, the permuted matrix.