anchor.diff:              crossprod(2) = za*xb-xa*zb
               crossprod(3) = xa*yb-ya*xb
               norm2_crossprod=crossprod(1)**2+ crossprod(2)**2+ crossprod(3)**2
  -            !print "(A,6F21.16)","xa xb:",xa,ya,za,xb,yb,zb
               ! check for singularity  
  -            ! TODO this check is viscous model dependent(e.g. crossprod)... have to go towards different funcitons soon..
  -            ! to avoid singularity, save a bit of computation and use limit values
               if (denominator<PRECISION_UI .or. norm2_crossprod<PRECISION_UI) then
                  !--- Exactly on the Singularity, velocity is zero
                  !Uind(1:3)=0.0_ReKi
  
positive.code:          Uind_out(1:3,icp) = Uind_out(1:3,icp)+Uind(1:3)
        end do ! Loop on segments
     enddo ! Loop on control points
     !$OMP END DO 
     !$OMP END PARALLEL
  end subroutine  
  
  
  end module FVW_BiotSavart
  
negative.code:          DP1        = CPs(:,icp)-P1;
           DP2        = CPs(:,icp)-P2
           Gam        = SegGamma(is)
           SmoothParam1= SmoothParam(is)
           ! --- inlining of ui_seg_11
           xa=DP1(1)
           ya=DP1(2)
           za=DP1(3)
  