SSWAP(3)        BLAS routine of NEC Numeric Library Collection        SSWAP(3)



NAME
       SSWAP - BLAS level one, Swaps two real vectors

SYNOPSIS
       SUBROUTINE SSWAP    ( n, x, incx, y, incy )

           INTEGER           n, incx, incy

           REAL              x, y


DESCRIPTION
       SSWAP  swaps two real vectors, it interchanges n values of vector x and
       vector y.  incx and incy specify the increment between two  consecutive
       elements of respectively vector x and y.

       This routine performs the following vector operation:

                 x <-> y

            where x and y are real vectors.

ARGUMENTS
       n       INTEGER. (input)
               Number of vector elements to be swapped.
               If n <= 0, this routine returns without computation.

       x       REAL, (input and output)
               Array of dimension (n-1) * |incx| + 1.

       incx    INTEGER. (input)
               Increment between elements of x.
               If incx = 0, the results will be unpredictable.

       y       REAL, (input and output)
               array of dimension (n-1) * |incy| + 1. Vector to be swapped.

       incy    INTEGER. (input)
               Increment between elements of y.
               If incy = 0, the results will be unpredictable.

NOTES
       This  routine  is  Level  1  Basic  Linear Algebra Subprograms (Level 1
       BLAS).

       When working backward (incx < 0 or incy < 0), each  routine  starts  at
       the end of the vector and moves backward, as follows:

            x(1-incx * (n-1)), x(1-incx * (n-2)), ..., x(1)

            y(1-incy * (n-1)), y(1-incy * (n-2)), ..., y(1)



BLAS routine                                                          SSWAP(3)