      DOUBLE PRECISION FUNCTION DNRM2( N, SX, INCX )
****************************************************************************
*                                                                          *
*   DATA PARALLEL BLAS based on MPL                                        *
*                                                                          *
*   Version 1.0   1/9-92 ,                                                 *
*   For MasPar MP-1 computers                                              *
*                                                                          *
*   para//ab, University of Bergen, NORWAY                                 *
*                                                                          *
*   These programs must be called using F90 style array syntax.            *
*   Note that the F77 style calling sequence has been retained             *
*   in this version for compatibility reasons, be aware that               *
*   parameters related to the array dimensions and shape therefore may     *
*   be redundant and without any influence.                                *
*   The calling sequence may be changed in a future version.               *
*   Please report any BUGs, ideas for improvement or other                 *
*   comments to                                                            *
*                    adm@parallab.uib.no                                   *
*                                                                          *
*   Future versions may then reflect your suggestions.                     *
*   The most current version of this software is available                 *
*   from netlib@nac.no , send the message `send index from maspar'         *
*                                                                          *
*   REVISIONS:                                                             *
*                                                                          *
****************************************************************************
      implicit none
*
*     compute the 2-norm of a vector.
*     written by tor sorevik, 9/25/92.
*
*     .. Scalar Arguments ..
      INTEGER                         INCX,  N
*     ..
*     .. Array Arguments ..
      double precision, array(:) :: SX
*     ..
*     .. Local Scalars ..
      INTEGER           m,ix,jx
*     ..
*     .. Intrinsic Functions ..
      INTRINSIC                       dotproduct
*     ..
*     .. Executable Statements ..
*
      DNRM2 = 0.0D0
      IF( N.LE.0 ) return
*
*        code for increment equal to 1
*
      IF( INCX.EQ.1 ) then
        dnrm2 = dotproduct(sx(1:n), sx(1:n))
      else
*
*        code for increments not equal to 1
*
        m  = n - 1
        ix = 1
        jx = 1 + m * incx
*
        if ( incx .lt. 0 ) then
        ix = 1 - m * incx
        jx = 1
        endif
*
        dnrm2 = dotproduct(sx(ix:jx:incx),sx(ix:jx:incx))
      endif
*
*	taking the squareroot and returning
*
      dnrm2 = sqrt(dnrm2)
      RETURN
*
*     End of DNRM2 .
*
      END